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Hindawi Publishing Corporation Journal of Mathematics Volume 2013, Article ID 967045, 5 pages http://dx.doi.org/10.1155/2013/967045 Research Article Weak Contraction Condition Involving Cubic Terms of (, ) under the Fixed Point Consideration Penumurthy Parvateesam Murthy and K. N. V. V. Vara Prasad Department of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur, Chhattisgrah 495009, India Correspondence should be addressed to K. N. V. V. Vara Prasad; [email protected] Received 31 January 2013; Accepted 14 April 2013 Academic Editor: Krassimir T. Atanassov Copyright © 2013 P. P. Murthy and K. N. V. V. Vara Prasad. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A fixed point theorem is presented for single-valued map with using generalized -weak contractive condition involving various combinations of (, ) on a complete metric space. Our result is an extension as well as a generalization of Alber and Guerre- Delabriere (1997) in particular. It also generalizes the results of Rhoades (2001), Choudhury and Dutta, (2000), and Dutta and Choudhury, (2008). 1. Introduction Let (, ) be a metric space. A map : is a contraction if, for each , , there exists a constant ∈ (0, 1) such that (, ) ≤ (, ). A map :→ is a -weak contraction if, for each , ∈ , there exists a function : [0, ∞) → [0, ∞), () > 0 for all >0 and (0) = 0 such that (, ) ≤ (, ) − ((, )). In [1] Alber and Guerre-Delabriere introduced the con- cept of weak contraction in Hilbert spaces. Rhoades [2] has shown that the result which Alber and Guerre-Delabriere had proved in [2] is also valid in complete metric spaces. In this paper we introduced generalized -weak contrac- tive condition involving various combinations of (, ). Our result is an extension as well as a generalization of Alber and Guerre-Delabriere [1] and Rhoades [2] in particular. It also generalizes the results of [3, 4]. Now, We state the result of Rhoades as follows. eorem 1 (see [2, eorem 2]). Let (, ) be a complete metric space, and let be a -weak contraction on : [0, +∞) → [0, +∞) which is a continuous and nondecreasing function with () > 0 for all ∈ (0, ∞) and (0) = 0 then has a unique fixed point in . If one takes () = (1 − ), where 0<<1, then weak contraction reduces to contraction mapping. In this paper, a new type of inequality is introduced with cubic terms involving (0) called a “generalized -weak contractive condition with cubic terms involving ”. Let (, ) be a metric space and a self-map of satisfying the following condition: [1 + (, )] 2 (, ) max { 1 2 [ 2 (, ) (, ) + (, ) 2 (, )] , (, ) (, ) (, ) , (, ) (, ) (, ) } + (, ) − ( (, )) , (1) where (, ) = max{ 2 (, ) , (, ) (, ) , (, ) (, ) , 1 2 [ (, ) (, ) + (, ) (, )]} (2)

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Page 1: Research Article Weak Contraction Condition …downloads.hindawi.com/journals/jmath/2013/967045.pdfDepartment of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur,

Hindawi Publishing CorporationJournal of MathematicsVolume 2013 Article ID 967045 5 pageshttpdxdoiorg1011552013967045

Research ArticleWeak Contraction Condition Involving Cubic Terms of119889(119909 119910) under the Fixed Point Consideration

Penumurthy Parvateesam Murthy and K N V V Vara Prasad

Department of Pure and Applied Mathematics Guru Ghasidas Vishwavidyalaya Bilaspur Chhattisgrah 495009 India

Correspondence should be addressed to K N V V Vara Prasad kvaraprasad71gmailcom

Received 31 January 2013 Accepted 14 April 2013

Academic Editor Krassimir T Atanassov

Copyright copy 2013 P P Murthy and K N V V Vara PrasadThis is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

A fixed point theorem is presented for single-valued map with using generalized 120593-weak contractive condition involving variouscombinations of 119889(119909 119910) on a complete metric space Our result is an extension as well as a generalization of Alber and Guerre-Delabriere (1997) in particular It also generalizes the results of Rhoades (2001) Choudhury and Dutta (2000) and Dutta andChoudhury (2008)

1 Introduction

Let (119883 119889) be a metric space A map 119879 119883 rarr 119883 is acontraction if for each 119909 119910 isin 119883 there exists a constant119896 isin (0 1) such that 119889(119879119909 119879119910) le 119896 119889(119909 119910)

A map 119879 119883 rarr 119883 is a 120593-weak contraction if for each119909 119910 isin 119864 there exists a function 120593 [0infin) rarr [0infin) 120593(119905) gt0 for all 119905 gt 0 and 120593(0) = 0 such that 119889(119879119909 119879119910) le 119889(119909 119910) minus

120593(119889(119909 119910))In [1] Alber and Guerre-Delabriere introduced the con-

cept of weak contraction in Hilbert spaces Rhoades [2] hasshown that the result whichAlber andGuerre-Delabriere hadproved in [2] is also valid in complete metric spaces

In this paper we introduced generalized 120593-weak contrac-tive condition involving various combinations of 119889(119909 119910) Ourresult is an extension as well as a generalization of Alber andGuerre-Delabriere [1] and Rhoades [2] in particular It alsogeneralizes the results of [3 4]

Now We state the result of Rhoades as follows

Theorem 1 (see [2 Theorem 2]) Let (119883 119889) be a completemetric space and let 119879 be a 120593-weak contraction on 119883 120593

[0 +infin) rarr [0 +infin)which is a continuous and nondecreasingfunction with 120593(119905) gt 0 for all 119905 isin (0infin) and 120593(0) = 0 then 119879

has a unique fixed point in119883If one takes 120593(119905) = (1 minus 119896)119905 where 0 lt 119896 lt 1 then weak

contraction reduces to contraction mapping

In this paper a new type of inequality is introduced withcubic terms involving 119901(ge0) called a ldquogeneralized 120593-weakcontractive condition with cubic terms involving 119901rdquo

Let (119883 119889) be ametric space and119879 a self-map of119883 satisfyingthe following condition

[1 + 119901119889 (119909 119910)] 1198892(119879119909 119879119910)

le 119901max 1

2[1198892(119909 119879119909) 119889 (119910 119879119910) + 119889 (119909 119879119909) 119889

2(119910 119879119910)]

119889 (119909 119879119909) 119889 (119909 119879119910) 119889 (119910 119879119909)

119889 (119909 119879119910) 119889 (119910 119879119909) 119889 (119910 119879119910)

+ 119898 (119909 119910) minus 120593 (119898 (119909 119910))

(1)

where

119898(119909 119910)

=max1198892 (119909 119910) 119889 (119909 119879119909) 119889 (119910 119879119910) 119889 (119909 119879119910) 119889 (119910 119879119909)

1

2[119889 (119909 119879119909) 119889 (119909 119879119910) + 119889 (119910 119879119909) 119889 (119910 119879119910)]

(2)

2 Journal of Mathematics

119901 ge 0 is a real number is and 120593 [0infin) rarr [0infin) is acontinuous function with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 foreach 119905 gt 0

2 Main Result

Lemma 2 Let 119879 be a self map of a metric space 119883 satisfying(1) For any sequence 119909

119899 in 119883 defined by 119909

119899+1= 119879119909119899 119899 ge 0

Then the sequence 119909119899 is Cauchy in119883

Proof Let 1199090

isin 119883 be an arbitrary point Constructing thesequence 119909

119899 follows

119909119899+1

= 119879119909119899 119899 isin 119873

0 (3)

If 119909119899= 119909119899+1

for some 119899 then trivially 119879 has a fixed point Weassume 119909

119899+1= 119909119899 for all 119899 isin 119873

0 We write 120572

119899= 119889(119909

119899 119909119899+1

)First we prove that 120572

119899 is a nonincreasing sequence and

converges to 0Case 1 If 119899 is even taking 119909 = 119909

2119899and 119910 = 119909

2119899+1in (1) we get

[1 + 119901 119889 (1199092119899 1199092119899+1

)] 1198892(1198791199092119899 1198791199092119899+1

)

le 119901max 1

2[1198892(1199092119899 1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)

+119889 (1199092119899 1198791199092119899) 1198892(1199092119899+1

1198791199092119899+1

)]

119889 (1199092119899 1198791199092119899) 119889 (1199092119899 1198791199092119899+1

)

times 119889 (1199092119899+1

1198791199092119899) 119889 (119909

2119899 1198791199092119899+1

)

times 119889 (1199092119899+1

1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)

+ 119898 (1199092119899 1199092119899+1

) minus 120593 (119898 (1199092119899 1199092119899+1

))

(4)

where

119898(1199092119899 1199092119899+1

)

= max 1198892 (1199092119899 1199092119899+1

) 119889 (1199092119899 1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)

119889 (1199092119899 1198791199092119899+1

) 119889 (1199092119899+1

1198791199092119899)

1

2[119889 (1199092119899 1198791199092119899) 119889 (1199092119899 1198791199092119899+1

)

+119889 (1199092119899+1

1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)]

(5)

By using (3) we get

[1 + 119901 119889 (1199092119899 1199092119899+1

)] 1198892(1199092119899+1

1199092119899+2

)

le 119901max 1

2[1198892(1199092119899 1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)

+119889 (1199092119899 1199092119899+1

) 1198892(1199092119899+1

1199092119899+2

)]

119889 (1199092119899 1199092119899+1

) 119889 (1199092119899 1199092119899+2

)

times 119889 (1199092119899+1

1199092119899+1

) 119889 (1199092119899 1199092119899+2

)

times 119889 (1199092119899+1

1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)

+ 119898 (1199092119899 1199092119899+1

) minus 120593 (119898 (1199092119899 1199092119899+1

))

(6)

where

119898(1199092119899 1199092119899+1

)

= max 1198892 (1199092119899 1199092119899+1

) 119889 (1199092119899 1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)

119889 (1199092119899 1199092119899+2

) 119889 (1199092119899+1

1199092119899+1

)

1

2[119889 (1199092119899 1199092119899+1

) 119889 (1199092119899 1199092119899+2

)

+119889 (1199092119899+1

1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)]

(7)

Now consider 1205722119899

= 119889(1199092119899 1199092119899+1

) then we have

[1 + 1199011205722119899] 1205722

2119899+1

le 119901max 1

2[1205722

21198991205722119899+1

+ 12057221198991205722

2119899+1] 0 0

+ 119898 (1199092119899 1199092119899+1

) minus 120593 (119898 (1199092119899 1199092119899+1

))

(8)

where119898(1199092119899 1199092119899+1

) = max12057222119899 12057221198991205722119899+1

0 (12)[1205722119899119889(1199092119899

1199092119899+2

) + 0]By triangular inequality and using property of 120593 we get

119889 (1199092119899 1199092119899+2

) le 119889 (1199092119899 1199092119899+1

) + 119889 (1199092119899+1

1199092119899+2

)

= 1205722119899

+ 1205722119899+1

(9)

Then

119898(1199092119899 1199092119899+1

) le 1198981015840(119909 119910)

= max 12057222119899 1205722119899+1

1205722119899 0

1

21205722119899

(1205722119899

+ 1205722119899+1

) 0

(10)

If 1205722119899

lt 1205722119899+1

then (8) reduces to 1199011205722

2119899+1le 119901120572

2

2119899+1minus

120593(1205722

2119899+1) a contradiction Thus 120572

2

2119899+1le 1205722

2119899implies that

1205722119899+1

le 1205722119899

In a similar way if 119899 is odd we can obtain 1205722119899+2

lt 1205722119899+1

It follows that the sequence 120572

119899 is decreasing

Let lim119899rarrinfin

120572119899= 119903 for some 119903 ge 0

Journal of Mathematics 3

Suppose 119903 gt 0 then from inequality (1) we have

[1 + 119901 119889 (119909119899 119909119899+1

)] 1198892(119879119909119899 119879119909119899+1

)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

+119889 (119909119899 119879119909119899) 1198892(119909119899+1

119879119909119899+1

)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899+1

)

times 119889 (119909119899+1

119879119909119899) 119889 (119909

119899 119879119909119899+1

)

times119889 (119909119899+1

119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

+ 119898 (119909119899 119909119899+1

) minus 120593 (119898 (119909119899 119909119899+1

))

(11)

where119898(119909119899 119909119899+1

)

= max 1198892 (119909119899 119909119899+1

) 119889 (119909119899 119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

119889 (119909119899 119879119909119899+1

) 119889 (119909119899+1

119879119909119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899+1

)

+119889 (119909119899+1

119879119909119899) 119889 (119909119899+1

119879119909119899+1

)]

(12)

By using (3) we get

[1 + 119901119889 (119909119899 119909119899+1

)] 1198892(119909119899+1

119909119899+2

)

le 119901max 1

2[1198892(119909119899 119909119899+1

) 119889 (119909119899+1

119909119899+2

)

+119889 (119909119899 119909119899+1

) 1198892(119909119899+1

119909119899+2

)]

119889 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

)

119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

) 119889 (119909119899+1

119909119899+2

)

+ 119898 (119909119899 119909119899+1

) minus 120593 (119898 (119909119899 119909119899+1

))

(13)

where119898(119909119899 119909119899+1

)

= max 1198892 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+1

) 119889 (119909119899+1

119909119899+2

)

119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

)

1

2[119889 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+2

)

+119889 (119909119899+1

119909119899+1

) 119889 (119909119899+1

119909119899+2

)]

(14)

Using triangular inequality and property of 120593 and takinglimits 119899 rarr infin we get

[1 + 119901119903] 1199032le 1199011199033+ 1199032minus 120593 (119903

2) (15)

Then 120593(1199032) le 0 since 119903 is positive then by the property of 120593

we get 119903 = 0 We conclude that

lim119899rarrinfin

120572119899= lim119899rarrinfin

119889 (119909119899 119909119899+1

) = 119903 = 0 (16)

Now we show that 119909119899 is a Cauchy sequence Suppose

we assume that 119909119899 is not a Cauchy sequence then there is

120576 gt 0 for which we can find two sequences of positive integers119898(119896) and 119899(119896) such that for all positive integers 119896 119899(119896) gt

119898(119896) gt 119896

119889 (119909119898(119896)

119909119899(119896)

) ge 120598 119889 (119909119898(119896)

119909119899(119896)minus1

) lt 120598 (17)

Now

120598 le 119889 (119909119898(119896)

119909119899(119896)

) le 119889 (119909119898(119896)

119909119899(119896)minus1

) + 119889 (119909119899(119896)minus1

119909119899(119896)

)

(18)

Letting 119896 rarr infin we get

lim119896rarrinfin

119889 (119909119898(119896)

119909119899(119896)

) = 120598 (19)

Now from the triangular inequality we have1003816100381610038161003816119889 (119909119899(119896)

119909119898(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816 le 119889 (119909

119898(119896) 119909119898(119896)+1

)

(20)

Taking limits as 119896 rarr infin and using (16) and (19) we have

lim119896rarrinfin

119889 (119909119899(119896)

119909119898(119896)+1

) = 120598 (21)

Again from the triangular inequality we have1003816100381610038161003816119889 (119909119898(119896)

119909119899(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816 le 119889 (119909

119899(119896) 119909119899(119896)+1

)

(22)

Taking limits as 119896 rarr infin and using (16) and (19) we have

lim119896rarrinfin

119889 (119909119898(119896)

119909119899(119896)+1

) = 120598 (23)

Again by using triangular inequality we have1003816100381610038161003816119889 (119909119898(119896)+1

119909119899(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816

le 119889 (119909119898(119896)

119909119898(119896)+1

) + 119889 (119909119899(119896)

119909119899(119896)+1

)

(24)

Taking limit 119896 rarr infin in the above inequality and using (16)and (19) we have

lim119896rarrinfin

119889 (119909119899(119896)+1

119909119898(119896)+1

) = 120598 (25)

Again putting 119909 = 119909119898(119896)

and 119910 = 119909119899(119896)

in (1) we get

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119879119909119898(119896)

119879119909119899(119896)

)

le 119901 1

2[1198892(119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

+119889 (119909119898(119896)

119879119909119898(119896)

) 1198892(119909119899(119896)

119879119909119899(119896)

)]

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(26)

4 Journal of Mathematics

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

1

2[119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

)

+119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)]

(27)

Using (3) then we obtain

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119909119898(119896)+1

119909119899(119896)+1

)

le 119901 1

2[1198892(119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+119889 (119909119898(119896)

119909119898(119896)+1

) 1198892(119909119899(119896)

119909119899(119896)+1

)]

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(28)

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

119889 (119909119898(119896)

119909119899(119896)+1

) 119889 (119909119899(119896)

119909119898(119896)+1

)

1

2[119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

+119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)]

(29)

Letting 119896 rarr infin and using (16)ndash(25) we get

[1 + 119901120598] 1205982

le 119901max 1

2[0 + 0] 0 0 + 120598

2minus 120593 (120598

2)

= 1205982minus 120593 (120598

2)

(30)

a contradiction Thus 119909119899 is a Cauchy in119883

Theorem 3 Let 119879 be a self-map of a complete metric space 119883satisfying (1) Then 119879 has a unique fixed point in119883

Proof From Lemma 2 the sequence 119909119899 is a Cauchy in 119883

Since (119883 119889) is a complete metric space then there exists apoint 119911 isin 119883 such that

lim119899rarrinfin

119909119899= 119911 (31)

Now we prove that 119911 is a fixed point of 119879Taking 119909 = 119909

119899and 119910 = 119911 in (1) we have

[1 + 119901119889 (119909119899 119911)] 119889

2(119879119909119899 119879119911)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119911 119879119911)

+119889 (119909119899 119879119909119899) 1198892(119911 119879119911)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119911) 119889 (119911 119879119909

119899)

119889 (119909119899 119879119911) 119889 (119911 119879119909

119899) 119889 (119911 119879119911)

+ 119898 (119909119899 119911) minus 120593 (119898 (119909

119899 119911))

(32)

where

119898(119909119899 119911)

= max 1198892 (119909119899 119911)

119889 (119909119899 119879119909119899) 119889 (119911 119879119911) 119889 (119909

119899 119879119911) 119889 (119911 119879119909

119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899)

+119889 (119911 119879119909119899) 119889 (119911 119879119911)]

(33)

Using (31) and (3) we get

[1 + 119901119889 (119911 119911)] 1198892(119911 119879119911)

le 119901max 1

2[1198892(119911 119911) 119889 (119911 119879119911) + 119889 (119911 119911) 119889

2(119911 119879119911)]

119889 (119911 119911) 119889 (119911 119879119911) 119889 (119911 119911)

119889 (119911 119879119911) 119889 (119911 119911) 119889 (119911 119879119911)

+ 119898 (119911 119911) minus 120593 (119898 (119911 119911))

(34)

Hence 1198892(119911 119879119911) le 0 rArr 119879119911 = 119911Then 119879 has a fixed point in119883To prove the uniqueness of the fixed point we assume that

1199111and 1199112are two fixed points of 119879 Taking 119909 = 119911

1and 119910 = 119911

2

in (1) we easily get 119889(1199111 1199112) = 0 wich implies that 119911

1= 1199112

Therefore 119879 has a unique fixed point in119883

Corollary 4 Let 119879 be a self-map of a complete metric space119883satisfying the condition

1198892(119879119909 119879119910) le 119898 (119909 119910) minus 120593 (119898 (119909 119910)) (35)

Journal of Mathematics 5

where

119898(119909 119910)

= max 1198892 (119909 119910) 119889 (119909 119879119909) 119889 (119910 119879119910)

119889 (119909 119879119910) 119889 (119910 119879119909)

1

2[119889 (119909 119879119909) 119889 (119909 119879119910) + 119889 (119910 119879119909) 119889 (119910 119879119910)]

(36)

for all 119909 119910 isin 119883 and 120593 [0infin) rarr [0infin) is a continuousfunction with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 for each 119905 gt 0Then 119879 has a unique fixed point in119883

Proof 119901 = 0 in Theorem 3 we have the result

Now we give an example to support our result

Example 5 Let119883 = 0 1 2 and let 119889 be the usual metric on119883 Let 119879 119883 rarr 119883 be defined by 1198790 = 1198791 = 0 and 1198792 = 1And define 120593 [0infin) rarr [0infin) by 120593(119905) = 1199052 For any valueof 119901 gt 0 and 119909 119910 isin 119883 then it is easy to verify that inequality(1) holds HenceTheorem 3 holds well

Acknowledgment

Penumurthy Parvateesam Murthy is thankful to the Uni-versity Grants Commission New Delhi India for financialassistance throughMajor Reserch Project File no 42-322013(SR)

References

[1] Y I Alber and S Guerre-Delabriere ldquoPrinciple of weaklycontractive maps in Hilbert spacesrdquo in New Results in OperatorTheory and its Applications I Gohberg and Y Lybich Eds vol98 of Operator Theory Advances and Applications pp 7ndash22Birkhauser Basel Switzerland 1997

[2] B E Rhoades ldquoSome theorems on weakly contractive mapsrdquoNonlinear Analysis Theory Methods amp Applications A Theoryand Methods vol 47 no 4 pp 2683ndash2693 2001

[3] B S Choudhury and P N Dutta ldquoA unified fixed point resultin metric spaces involving a two variable functionrdquo Filomat no14 pp 43ndash48 2000

[4] P N Dutta and B S Choudhury ldquoA generalisation of con-traction principle in metric spacesrdquo Fixed Point Theory andApplications vol 2008 Article ID 406368 8 pages 2008

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Stochastic AnalysisInternational Journal of

Page 2: Research Article Weak Contraction Condition …downloads.hindawi.com/journals/jmath/2013/967045.pdfDepartment of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur,

2 Journal of Mathematics

119901 ge 0 is a real number is and 120593 [0infin) rarr [0infin) is acontinuous function with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 foreach 119905 gt 0

2 Main Result

Lemma 2 Let 119879 be a self map of a metric space 119883 satisfying(1) For any sequence 119909

119899 in 119883 defined by 119909

119899+1= 119879119909119899 119899 ge 0

Then the sequence 119909119899 is Cauchy in119883

Proof Let 1199090

isin 119883 be an arbitrary point Constructing thesequence 119909

119899 follows

119909119899+1

= 119879119909119899 119899 isin 119873

0 (3)

If 119909119899= 119909119899+1

for some 119899 then trivially 119879 has a fixed point Weassume 119909

119899+1= 119909119899 for all 119899 isin 119873

0 We write 120572

119899= 119889(119909

119899 119909119899+1

)First we prove that 120572

119899 is a nonincreasing sequence and

converges to 0Case 1 If 119899 is even taking 119909 = 119909

2119899and 119910 = 119909

2119899+1in (1) we get

[1 + 119901 119889 (1199092119899 1199092119899+1

)] 1198892(1198791199092119899 1198791199092119899+1

)

le 119901max 1

2[1198892(1199092119899 1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)

+119889 (1199092119899 1198791199092119899) 1198892(1199092119899+1

1198791199092119899+1

)]

119889 (1199092119899 1198791199092119899) 119889 (1199092119899 1198791199092119899+1

)

times 119889 (1199092119899+1

1198791199092119899) 119889 (119909

2119899 1198791199092119899+1

)

times 119889 (1199092119899+1

1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)

+ 119898 (1199092119899 1199092119899+1

) minus 120593 (119898 (1199092119899 1199092119899+1

))

(4)

where

119898(1199092119899 1199092119899+1

)

= max 1198892 (1199092119899 1199092119899+1

) 119889 (1199092119899 1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)

119889 (1199092119899 1198791199092119899+1

) 119889 (1199092119899+1

1198791199092119899)

1

2[119889 (1199092119899 1198791199092119899) 119889 (1199092119899 1198791199092119899+1

)

+119889 (1199092119899+1

1198791199092119899) 119889 (1199092119899+1

1198791199092119899+1

)]

(5)

By using (3) we get

[1 + 119901 119889 (1199092119899 1199092119899+1

)] 1198892(1199092119899+1

1199092119899+2

)

le 119901max 1

2[1198892(1199092119899 1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)

+119889 (1199092119899 1199092119899+1

) 1198892(1199092119899+1

1199092119899+2

)]

119889 (1199092119899 1199092119899+1

) 119889 (1199092119899 1199092119899+2

)

times 119889 (1199092119899+1

1199092119899+1

) 119889 (1199092119899 1199092119899+2

)

times 119889 (1199092119899+1

1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)

+ 119898 (1199092119899 1199092119899+1

) minus 120593 (119898 (1199092119899 1199092119899+1

))

(6)

where

119898(1199092119899 1199092119899+1

)

= max 1198892 (1199092119899 1199092119899+1

) 119889 (1199092119899 1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)

119889 (1199092119899 1199092119899+2

) 119889 (1199092119899+1

1199092119899+1

)

1

2[119889 (1199092119899 1199092119899+1

) 119889 (1199092119899 1199092119899+2

)

+119889 (1199092119899+1

1199092119899+1

) 119889 (1199092119899+1

1199092119899+2

)]

(7)

Now consider 1205722119899

= 119889(1199092119899 1199092119899+1

) then we have

[1 + 1199011205722119899] 1205722

2119899+1

le 119901max 1

2[1205722

21198991205722119899+1

+ 12057221198991205722

2119899+1] 0 0

+ 119898 (1199092119899 1199092119899+1

) minus 120593 (119898 (1199092119899 1199092119899+1

))

(8)

where119898(1199092119899 1199092119899+1

) = max12057222119899 12057221198991205722119899+1

0 (12)[1205722119899119889(1199092119899

1199092119899+2

) + 0]By triangular inequality and using property of 120593 we get

119889 (1199092119899 1199092119899+2

) le 119889 (1199092119899 1199092119899+1

) + 119889 (1199092119899+1

1199092119899+2

)

= 1205722119899

+ 1205722119899+1

(9)

Then

119898(1199092119899 1199092119899+1

) le 1198981015840(119909 119910)

= max 12057222119899 1205722119899+1

1205722119899 0

1

21205722119899

(1205722119899

+ 1205722119899+1

) 0

(10)

If 1205722119899

lt 1205722119899+1

then (8) reduces to 1199011205722

2119899+1le 119901120572

2

2119899+1minus

120593(1205722

2119899+1) a contradiction Thus 120572

2

2119899+1le 1205722

2119899implies that

1205722119899+1

le 1205722119899

In a similar way if 119899 is odd we can obtain 1205722119899+2

lt 1205722119899+1

It follows that the sequence 120572

119899 is decreasing

Let lim119899rarrinfin

120572119899= 119903 for some 119903 ge 0

Journal of Mathematics 3

Suppose 119903 gt 0 then from inequality (1) we have

[1 + 119901 119889 (119909119899 119909119899+1

)] 1198892(119879119909119899 119879119909119899+1

)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

+119889 (119909119899 119879119909119899) 1198892(119909119899+1

119879119909119899+1

)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899+1

)

times 119889 (119909119899+1

119879119909119899) 119889 (119909

119899 119879119909119899+1

)

times119889 (119909119899+1

119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

+ 119898 (119909119899 119909119899+1

) minus 120593 (119898 (119909119899 119909119899+1

))

(11)

where119898(119909119899 119909119899+1

)

= max 1198892 (119909119899 119909119899+1

) 119889 (119909119899 119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

119889 (119909119899 119879119909119899+1

) 119889 (119909119899+1

119879119909119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899+1

)

+119889 (119909119899+1

119879119909119899) 119889 (119909119899+1

119879119909119899+1

)]

(12)

By using (3) we get

[1 + 119901119889 (119909119899 119909119899+1

)] 1198892(119909119899+1

119909119899+2

)

le 119901max 1

2[1198892(119909119899 119909119899+1

) 119889 (119909119899+1

119909119899+2

)

+119889 (119909119899 119909119899+1

) 1198892(119909119899+1

119909119899+2

)]

119889 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

)

119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

) 119889 (119909119899+1

119909119899+2

)

+ 119898 (119909119899 119909119899+1

) minus 120593 (119898 (119909119899 119909119899+1

))

(13)

where119898(119909119899 119909119899+1

)

= max 1198892 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+1

) 119889 (119909119899+1

119909119899+2

)

119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

)

1

2[119889 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+2

)

+119889 (119909119899+1

119909119899+1

) 119889 (119909119899+1

119909119899+2

)]

(14)

Using triangular inequality and property of 120593 and takinglimits 119899 rarr infin we get

[1 + 119901119903] 1199032le 1199011199033+ 1199032minus 120593 (119903

2) (15)

Then 120593(1199032) le 0 since 119903 is positive then by the property of 120593

we get 119903 = 0 We conclude that

lim119899rarrinfin

120572119899= lim119899rarrinfin

119889 (119909119899 119909119899+1

) = 119903 = 0 (16)

Now we show that 119909119899 is a Cauchy sequence Suppose

we assume that 119909119899 is not a Cauchy sequence then there is

120576 gt 0 for which we can find two sequences of positive integers119898(119896) and 119899(119896) such that for all positive integers 119896 119899(119896) gt

119898(119896) gt 119896

119889 (119909119898(119896)

119909119899(119896)

) ge 120598 119889 (119909119898(119896)

119909119899(119896)minus1

) lt 120598 (17)

Now

120598 le 119889 (119909119898(119896)

119909119899(119896)

) le 119889 (119909119898(119896)

119909119899(119896)minus1

) + 119889 (119909119899(119896)minus1

119909119899(119896)

)

(18)

Letting 119896 rarr infin we get

lim119896rarrinfin

119889 (119909119898(119896)

119909119899(119896)

) = 120598 (19)

Now from the triangular inequality we have1003816100381610038161003816119889 (119909119899(119896)

119909119898(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816 le 119889 (119909

119898(119896) 119909119898(119896)+1

)

(20)

Taking limits as 119896 rarr infin and using (16) and (19) we have

lim119896rarrinfin

119889 (119909119899(119896)

119909119898(119896)+1

) = 120598 (21)

Again from the triangular inequality we have1003816100381610038161003816119889 (119909119898(119896)

119909119899(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816 le 119889 (119909

119899(119896) 119909119899(119896)+1

)

(22)

Taking limits as 119896 rarr infin and using (16) and (19) we have

lim119896rarrinfin

119889 (119909119898(119896)

119909119899(119896)+1

) = 120598 (23)

Again by using triangular inequality we have1003816100381610038161003816119889 (119909119898(119896)+1

119909119899(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816

le 119889 (119909119898(119896)

119909119898(119896)+1

) + 119889 (119909119899(119896)

119909119899(119896)+1

)

(24)

Taking limit 119896 rarr infin in the above inequality and using (16)and (19) we have

lim119896rarrinfin

119889 (119909119899(119896)+1

119909119898(119896)+1

) = 120598 (25)

Again putting 119909 = 119909119898(119896)

and 119910 = 119909119899(119896)

in (1) we get

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119879119909119898(119896)

119879119909119899(119896)

)

le 119901 1

2[1198892(119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

+119889 (119909119898(119896)

119879119909119898(119896)

) 1198892(119909119899(119896)

119879119909119899(119896)

)]

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(26)

4 Journal of Mathematics

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

1

2[119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

)

+119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)]

(27)

Using (3) then we obtain

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119909119898(119896)+1

119909119899(119896)+1

)

le 119901 1

2[1198892(119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+119889 (119909119898(119896)

119909119898(119896)+1

) 1198892(119909119899(119896)

119909119899(119896)+1

)]

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(28)

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

119889 (119909119898(119896)

119909119899(119896)+1

) 119889 (119909119899(119896)

119909119898(119896)+1

)

1

2[119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

+119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)]

(29)

Letting 119896 rarr infin and using (16)ndash(25) we get

[1 + 119901120598] 1205982

le 119901max 1

2[0 + 0] 0 0 + 120598

2minus 120593 (120598

2)

= 1205982minus 120593 (120598

2)

(30)

a contradiction Thus 119909119899 is a Cauchy in119883

Theorem 3 Let 119879 be a self-map of a complete metric space 119883satisfying (1) Then 119879 has a unique fixed point in119883

Proof From Lemma 2 the sequence 119909119899 is a Cauchy in 119883

Since (119883 119889) is a complete metric space then there exists apoint 119911 isin 119883 such that

lim119899rarrinfin

119909119899= 119911 (31)

Now we prove that 119911 is a fixed point of 119879Taking 119909 = 119909

119899and 119910 = 119911 in (1) we have

[1 + 119901119889 (119909119899 119911)] 119889

2(119879119909119899 119879119911)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119911 119879119911)

+119889 (119909119899 119879119909119899) 1198892(119911 119879119911)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119911) 119889 (119911 119879119909

119899)

119889 (119909119899 119879119911) 119889 (119911 119879119909

119899) 119889 (119911 119879119911)

+ 119898 (119909119899 119911) minus 120593 (119898 (119909

119899 119911))

(32)

where

119898(119909119899 119911)

= max 1198892 (119909119899 119911)

119889 (119909119899 119879119909119899) 119889 (119911 119879119911) 119889 (119909

119899 119879119911) 119889 (119911 119879119909

119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899)

+119889 (119911 119879119909119899) 119889 (119911 119879119911)]

(33)

Using (31) and (3) we get

[1 + 119901119889 (119911 119911)] 1198892(119911 119879119911)

le 119901max 1

2[1198892(119911 119911) 119889 (119911 119879119911) + 119889 (119911 119911) 119889

2(119911 119879119911)]

119889 (119911 119911) 119889 (119911 119879119911) 119889 (119911 119911)

119889 (119911 119879119911) 119889 (119911 119911) 119889 (119911 119879119911)

+ 119898 (119911 119911) minus 120593 (119898 (119911 119911))

(34)

Hence 1198892(119911 119879119911) le 0 rArr 119879119911 = 119911Then 119879 has a fixed point in119883To prove the uniqueness of the fixed point we assume that

1199111and 1199112are two fixed points of 119879 Taking 119909 = 119911

1and 119910 = 119911

2

in (1) we easily get 119889(1199111 1199112) = 0 wich implies that 119911

1= 1199112

Therefore 119879 has a unique fixed point in119883

Corollary 4 Let 119879 be a self-map of a complete metric space119883satisfying the condition

1198892(119879119909 119879119910) le 119898 (119909 119910) minus 120593 (119898 (119909 119910)) (35)

Journal of Mathematics 5

where

119898(119909 119910)

= max 1198892 (119909 119910) 119889 (119909 119879119909) 119889 (119910 119879119910)

119889 (119909 119879119910) 119889 (119910 119879119909)

1

2[119889 (119909 119879119909) 119889 (119909 119879119910) + 119889 (119910 119879119909) 119889 (119910 119879119910)]

(36)

for all 119909 119910 isin 119883 and 120593 [0infin) rarr [0infin) is a continuousfunction with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 for each 119905 gt 0Then 119879 has a unique fixed point in119883

Proof 119901 = 0 in Theorem 3 we have the result

Now we give an example to support our result

Example 5 Let119883 = 0 1 2 and let 119889 be the usual metric on119883 Let 119879 119883 rarr 119883 be defined by 1198790 = 1198791 = 0 and 1198792 = 1And define 120593 [0infin) rarr [0infin) by 120593(119905) = 1199052 For any valueof 119901 gt 0 and 119909 119910 isin 119883 then it is easy to verify that inequality(1) holds HenceTheorem 3 holds well

Acknowledgment

Penumurthy Parvateesam Murthy is thankful to the Uni-versity Grants Commission New Delhi India for financialassistance throughMajor Reserch Project File no 42-322013(SR)

References

[1] Y I Alber and S Guerre-Delabriere ldquoPrinciple of weaklycontractive maps in Hilbert spacesrdquo in New Results in OperatorTheory and its Applications I Gohberg and Y Lybich Eds vol98 of Operator Theory Advances and Applications pp 7ndash22Birkhauser Basel Switzerland 1997

[2] B E Rhoades ldquoSome theorems on weakly contractive mapsrdquoNonlinear Analysis Theory Methods amp Applications A Theoryand Methods vol 47 no 4 pp 2683ndash2693 2001

[3] B S Choudhury and P N Dutta ldquoA unified fixed point resultin metric spaces involving a two variable functionrdquo Filomat no14 pp 43ndash48 2000

[4] P N Dutta and B S Choudhury ldquoA generalisation of con-traction principle in metric spacesrdquo Fixed Point Theory andApplications vol 2008 Article ID 406368 8 pages 2008

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 3: Research Article Weak Contraction Condition …downloads.hindawi.com/journals/jmath/2013/967045.pdfDepartment of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur,

Journal of Mathematics 3

Suppose 119903 gt 0 then from inequality (1) we have

[1 + 119901 119889 (119909119899 119909119899+1

)] 1198892(119879119909119899 119879119909119899+1

)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

+119889 (119909119899 119879119909119899) 1198892(119909119899+1

119879119909119899+1

)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899+1

)

times 119889 (119909119899+1

119879119909119899) 119889 (119909

119899 119879119909119899+1

)

times119889 (119909119899+1

119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

+ 119898 (119909119899 119909119899+1

) minus 120593 (119898 (119909119899 119909119899+1

))

(11)

where119898(119909119899 119909119899+1

)

= max 1198892 (119909119899 119909119899+1

) 119889 (119909119899 119879119909119899) 119889 (119909119899+1

119879119909119899+1

)

119889 (119909119899 119879119909119899+1

) 119889 (119909119899+1

119879119909119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899+1

)

+119889 (119909119899+1

119879119909119899) 119889 (119909119899+1

119879119909119899+1

)]

(12)

By using (3) we get

[1 + 119901119889 (119909119899 119909119899+1

)] 1198892(119909119899+1

119909119899+2

)

le 119901max 1

2[1198892(119909119899 119909119899+1

) 119889 (119909119899+1

119909119899+2

)

+119889 (119909119899 119909119899+1

) 1198892(119909119899+1

119909119899+2

)]

119889 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

)

119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

) 119889 (119909119899+1

119909119899+2

)

+ 119898 (119909119899 119909119899+1

) minus 120593 (119898 (119909119899 119909119899+1

))

(13)

where119898(119909119899 119909119899+1

)

= max 1198892 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+1

) 119889 (119909119899+1

119909119899+2

)

119889 (119909119899 119909119899+2

) 119889 (119909119899+1

119909119899+1

)

1

2[119889 (119909119899 119909119899+1

) 119889 (119909119899 119909119899+2

)

+119889 (119909119899+1

119909119899+1

) 119889 (119909119899+1

119909119899+2

)]

(14)

Using triangular inequality and property of 120593 and takinglimits 119899 rarr infin we get

[1 + 119901119903] 1199032le 1199011199033+ 1199032minus 120593 (119903

2) (15)

Then 120593(1199032) le 0 since 119903 is positive then by the property of 120593

we get 119903 = 0 We conclude that

lim119899rarrinfin

120572119899= lim119899rarrinfin

119889 (119909119899 119909119899+1

) = 119903 = 0 (16)

Now we show that 119909119899 is a Cauchy sequence Suppose

we assume that 119909119899 is not a Cauchy sequence then there is

120576 gt 0 for which we can find two sequences of positive integers119898(119896) and 119899(119896) such that for all positive integers 119896 119899(119896) gt

119898(119896) gt 119896

119889 (119909119898(119896)

119909119899(119896)

) ge 120598 119889 (119909119898(119896)

119909119899(119896)minus1

) lt 120598 (17)

Now

120598 le 119889 (119909119898(119896)

119909119899(119896)

) le 119889 (119909119898(119896)

119909119899(119896)minus1

) + 119889 (119909119899(119896)minus1

119909119899(119896)

)

(18)

Letting 119896 rarr infin we get

lim119896rarrinfin

119889 (119909119898(119896)

119909119899(119896)

) = 120598 (19)

Now from the triangular inequality we have1003816100381610038161003816119889 (119909119899(119896)

119909119898(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816 le 119889 (119909

119898(119896) 119909119898(119896)+1

)

(20)

Taking limits as 119896 rarr infin and using (16) and (19) we have

lim119896rarrinfin

119889 (119909119899(119896)

119909119898(119896)+1

) = 120598 (21)

Again from the triangular inequality we have1003816100381610038161003816119889 (119909119898(119896)

119909119899(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816 le 119889 (119909

119899(119896) 119909119899(119896)+1

)

(22)

Taking limits as 119896 rarr infin and using (16) and (19) we have

lim119896rarrinfin

119889 (119909119898(119896)

119909119899(119896)+1

) = 120598 (23)

Again by using triangular inequality we have1003816100381610038161003816119889 (119909119898(119896)+1

119909119899(119896)+1

) minus 119889 (119909119898(119896)

119909119899(119896)

)1003816100381610038161003816

le 119889 (119909119898(119896)

119909119898(119896)+1

) + 119889 (119909119899(119896)

119909119899(119896)+1

)

(24)

Taking limit 119896 rarr infin in the above inequality and using (16)and (19) we have

lim119896rarrinfin

119889 (119909119899(119896)+1

119909119898(119896)+1

) = 120598 (25)

Again putting 119909 = 119909119898(119896)

and 119910 = 119909119899(119896)

in (1) we get

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119879119909119898(119896)

119879119909119899(119896)

)

le 119901 1

2[1198892(119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

+119889 (119909119898(119896)

119879119909119898(119896)

) 1198892(119909119899(119896)

119879119909119899(119896)

)]

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(26)

4 Journal of Mathematics

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

1

2[119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

)

+119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)]

(27)

Using (3) then we obtain

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119909119898(119896)+1

119909119899(119896)+1

)

le 119901 1

2[1198892(119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+119889 (119909119898(119896)

119909119898(119896)+1

) 1198892(119909119899(119896)

119909119899(119896)+1

)]

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(28)

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

119889 (119909119898(119896)

119909119899(119896)+1

) 119889 (119909119899(119896)

119909119898(119896)+1

)

1

2[119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

+119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)]

(29)

Letting 119896 rarr infin and using (16)ndash(25) we get

[1 + 119901120598] 1205982

le 119901max 1

2[0 + 0] 0 0 + 120598

2minus 120593 (120598

2)

= 1205982minus 120593 (120598

2)

(30)

a contradiction Thus 119909119899 is a Cauchy in119883

Theorem 3 Let 119879 be a self-map of a complete metric space 119883satisfying (1) Then 119879 has a unique fixed point in119883

Proof From Lemma 2 the sequence 119909119899 is a Cauchy in 119883

Since (119883 119889) is a complete metric space then there exists apoint 119911 isin 119883 such that

lim119899rarrinfin

119909119899= 119911 (31)

Now we prove that 119911 is a fixed point of 119879Taking 119909 = 119909

119899and 119910 = 119911 in (1) we have

[1 + 119901119889 (119909119899 119911)] 119889

2(119879119909119899 119879119911)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119911 119879119911)

+119889 (119909119899 119879119909119899) 1198892(119911 119879119911)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119911) 119889 (119911 119879119909

119899)

119889 (119909119899 119879119911) 119889 (119911 119879119909

119899) 119889 (119911 119879119911)

+ 119898 (119909119899 119911) minus 120593 (119898 (119909

119899 119911))

(32)

where

119898(119909119899 119911)

= max 1198892 (119909119899 119911)

119889 (119909119899 119879119909119899) 119889 (119911 119879119911) 119889 (119909

119899 119879119911) 119889 (119911 119879119909

119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899)

+119889 (119911 119879119909119899) 119889 (119911 119879119911)]

(33)

Using (31) and (3) we get

[1 + 119901119889 (119911 119911)] 1198892(119911 119879119911)

le 119901max 1

2[1198892(119911 119911) 119889 (119911 119879119911) + 119889 (119911 119911) 119889

2(119911 119879119911)]

119889 (119911 119911) 119889 (119911 119879119911) 119889 (119911 119911)

119889 (119911 119879119911) 119889 (119911 119911) 119889 (119911 119879119911)

+ 119898 (119911 119911) minus 120593 (119898 (119911 119911))

(34)

Hence 1198892(119911 119879119911) le 0 rArr 119879119911 = 119911Then 119879 has a fixed point in119883To prove the uniqueness of the fixed point we assume that

1199111and 1199112are two fixed points of 119879 Taking 119909 = 119911

1and 119910 = 119911

2

in (1) we easily get 119889(1199111 1199112) = 0 wich implies that 119911

1= 1199112

Therefore 119879 has a unique fixed point in119883

Corollary 4 Let 119879 be a self-map of a complete metric space119883satisfying the condition

1198892(119879119909 119879119910) le 119898 (119909 119910) minus 120593 (119898 (119909 119910)) (35)

Journal of Mathematics 5

where

119898(119909 119910)

= max 1198892 (119909 119910) 119889 (119909 119879119909) 119889 (119910 119879119910)

119889 (119909 119879119910) 119889 (119910 119879119909)

1

2[119889 (119909 119879119909) 119889 (119909 119879119910) + 119889 (119910 119879119909) 119889 (119910 119879119910)]

(36)

for all 119909 119910 isin 119883 and 120593 [0infin) rarr [0infin) is a continuousfunction with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 for each 119905 gt 0Then 119879 has a unique fixed point in119883

Proof 119901 = 0 in Theorem 3 we have the result

Now we give an example to support our result

Example 5 Let119883 = 0 1 2 and let 119889 be the usual metric on119883 Let 119879 119883 rarr 119883 be defined by 1198790 = 1198791 = 0 and 1198792 = 1And define 120593 [0infin) rarr [0infin) by 120593(119905) = 1199052 For any valueof 119901 gt 0 and 119909 119910 isin 119883 then it is easy to verify that inequality(1) holds HenceTheorem 3 holds well

Acknowledgment

Penumurthy Parvateesam Murthy is thankful to the Uni-versity Grants Commission New Delhi India for financialassistance throughMajor Reserch Project File no 42-322013(SR)

References

[1] Y I Alber and S Guerre-Delabriere ldquoPrinciple of weaklycontractive maps in Hilbert spacesrdquo in New Results in OperatorTheory and its Applications I Gohberg and Y Lybich Eds vol98 of Operator Theory Advances and Applications pp 7ndash22Birkhauser Basel Switzerland 1997

[2] B E Rhoades ldquoSome theorems on weakly contractive mapsrdquoNonlinear Analysis Theory Methods amp Applications A Theoryand Methods vol 47 no 4 pp 2683ndash2693 2001

[3] B S Choudhury and P N Dutta ldquoA unified fixed point resultin metric spaces involving a two variable functionrdquo Filomat no14 pp 43ndash48 2000

[4] P N Dutta and B S Choudhury ldquoA generalisation of con-traction principle in metric spacesrdquo Fixed Point Theory andApplications vol 2008 Article ID 406368 8 pages 2008

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 4: Research Article Weak Contraction Condition …downloads.hindawi.com/journals/jmath/2013/967045.pdfDepartment of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur,

4 Journal of Mathematics

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)

119889 (119909119898(119896)

119879119909119899(119896)

) 119889 (119909119899(119896)

119879119909119898(119896)

)

1

2[119889 (119909119898(119896)

119879119909119898(119896)

) 119889 (119909119898(119896)

119879119909119899(119896)

)

+119889 (119909119899(119896)

119879119909119898(119896)

) 119889 (119909119899(119896)

119879119909119899(119896)

)]

(27)

Using (3) then we obtain

[1 + 119901119889 (119909119898(119896)

119909119899(119896)

)] 1198892(119909119898(119896)+1

119909119899(119896)+1

)

le 119901 1

2[1198892(119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+119889 (119909119898(119896)

119909119898(119896)+1

) 1198892(119909119899(119896)

119909119899(119896)+1

)]

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

times 119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

+ 119898 (119909119898(119896)

119909119899(119896)

) minus 120593 (119898 (119909119898(119896)

119909119899(119896)

))

(28)

where

119898(119909119898(119896)

119909119899(119896)

)

= max 1198892 (119909119898(119896)

119909119899(119896)

)

119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)

119889 (119909119898(119896)

119909119899(119896)+1

) 119889 (119909119899(119896)

119909119898(119896)+1

)

1

2[119889 (119909119898(119896)

119909119898(119896)+1

) 119889 (119909119898(119896)

119909119899(119896)+1

)

+119889 (119909119899(119896)

119909119898(119896)+1

) 119889 (119909119899(119896)

119909119899(119896)+1

)]

(29)

Letting 119896 rarr infin and using (16)ndash(25) we get

[1 + 119901120598] 1205982

le 119901max 1

2[0 + 0] 0 0 + 120598

2minus 120593 (120598

2)

= 1205982minus 120593 (120598

2)

(30)

a contradiction Thus 119909119899 is a Cauchy in119883

Theorem 3 Let 119879 be a self-map of a complete metric space 119883satisfying (1) Then 119879 has a unique fixed point in119883

Proof From Lemma 2 the sequence 119909119899 is a Cauchy in 119883

Since (119883 119889) is a complete metric space then there exists apoint 119911 isin 119883 such that

lim119899rarrinfin

119909119899= 119911 (31)

Now we prove that 119911 is a fixed point of 119879Taking 119909 = 119909

119899and 119910 = 119911 in (1) we have

[1 + 119901119889 (119909119899 119911)] 119889

2(119879119909119899 119879119911)

le 119901max 1

2[1198892(119909119899 119879119909119899) 119889 (119911 119879119911)

+119889 (119909119899 119879119909119899) 1198892(119911 119879119911)]

119889 (119909119899 119879119909119899) 119889 (119909119899 119879119911) 119889 (119911 119879119909

119899)

119889 (119909119899 119879119911) 119889 (119911 119879119909

119899) 119889 (119911 119879119911)

+ 119898 (119909119899 119911) minus 120593 (119898 (119909

119899 119911))

(32)

where

119898(119909119899 119911)

= max 1198892 (119909119899 119911)

119889 (119909119899 119879119909119899) 119889 (119911 119879119911) 119889 (119909

119899 119879119911) 119889 (119911 119879119909

119899)

1

2[119889 (119909119899 119879119909119899) 119889 (119909119899 119879119909119899)

+119889 (119911 119879119909119899) 119889 (119911 119879119911)]

(33)

Using (31) and (3) we get

[1 + 119901119889 (119911 119911)] 1198892(119911 119879119911)

le 119901max 1

2[1198892(119911 119911) 119889 (119911 119879119911) + 119889 (119911 119911) 119889

2(119911 119879119911)]

119889 (119911 119911) 119889 (119911 119879119911) 119889 (119911 119911)

119889 (119911 119879119911) 119889 (119911 119911) 119889 (119911 119879119911)

+ 119898 (119911 119911) minus 120593 (119898 (119911 119911))

(34)

Hence 1198892(119911 119879119911) le 0 rArr 119879119911 = 119911Then 119879 has a fixed point in119883To prove the uniqueness of the fixed point we assume that

1199111and 1199112are two fixed points of 119879 Taking 119909 = 119911

1and 119910 = 119911

2

in (1) we easily get 119889(1199111 1199112) = 0 wich implies that 119911

1= 1199112

Therefore 119879 has a unique fixed point in119883

Corollary 4 Let 119879 be a self-map of a complete metric space119883satisfying the condition

1198892(119879119909 119879119910) le 119898 (119909 119910) minus 120593 (119898 (119909 119910)) (35)

Journal of Mathematics 5

where

119898(119909 119910)

= max 1198892 (119909 119910) 119889 (119909 119879119909) 119889 (119910 119879119910)

119889 (119909 119879119910) 119889 (119910 119879119909)

1

2[119889 (119909 119879119909) 119889 (119909 119879119910) + 119889 (119910 119879119909) 119889 (119910 119879119910)]

(36)

for all 119909 119910 isin 119883 and 120593 [0infin) rarr [0infin) is a continuousfunction with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 for each 119905 gt 0Then 119879 has a unique fixed point in119883

Proof 119901 = 0 in Theorem 3 we have the result

Now we give an example to support our result

Example 5 Let119883 = 0 1 2 and let 119889 be the usual metric on119883 Let 119879 119883 rarr 119883 be defined by 1198790 = 1198791 = 0 and 1198792 = 1And define 120593 [0infin) rarr [0infin) by 120593(119905) = 1199052 For any valueof 119901 gt 0 and 119909 119910 isin 119883 then it is easy to verify that inequality(1) holds HenceTheorem 3 holds well

Acknowledgment

Penumurthy Parvateesam Murthy is thankful to the Uni-versity Grants Commission New Delhi India for financialassistance throughMajor Reserch Project File no 42-322013(SR)

References

[1] Y I Alber and S Guerre-Delabriere ldquoPrinciple of weaklycontractive maps in Hilbert spacesrdquo in New Results in OperatorTheory and its Applications I Gohberg and Y Lybich Eds vol98 of Operator Theory Advances and Applications pp 7ndash22Birkhauser Basel Switzerland 1997

[2] B E Rhoades ldquoSome theorems on weakly contractive mapsrdquoNonlinear Analysis Theory Methods amp Applications A Theoryand Methods vol 47 no 4 pp 2683ndash2693 2001

[3] B S Choudhury and P N Dutta ldquoA unified fixed point resultin metric spaces involving a two variable functionrdquo Filomat no14 pp 43ndash48 2000

[4] P N Dutta and B S Choudhury ldquoA generalisation of con-traction principle in metric spacesrdquo Fixed Point Theory andApplications vol 2008 Article ID 406368 8 pages 2008

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 5: Research Article Weak Contraction Condition …downloads.hindawi.com/journals/jmath/2013/967045.pdfDepartment of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur,

Journal of Mathematics 5

where

119898(119909 119910)

= max 1198892 (119909 119910) 119889 (119909 119879119909) 119889 (119910 119879119910)

119889 (119909 119879119910) 119889 (119910 119879119909)

1

2[119889 (119909 119879119909) 119889 (119909 119879119910) + 119889 (119910 119879119909) 119889 (119910 119879119910)]

(36)

for all 119909 119910 isin 119883 and 120593 [0infin) rarr [0infin) is a continuousfunction with 120593(119905) = 0 hArr 119905 = 0 and 120593(119905) gt 0 for each 119905 gt 0Then 119879 has a unique fixed point in119883

Proof 119901 = 0 in Theorem 3 we have the result

Now we give an example to support our result

Example 5 Let119883 = 0 1 2 and let 119889 be the usual metric on119883 Let 119879 119883 rarr 119883 be defined by 1198790 = 1198791 = 0 and 1198792 = 1And define 120593 [0infin) rarr [0infin) by 120593(119905) = 1199052 For any valueof 119901 gt 0 and 119909 119910 isin 119883 then it is easy to verify that inequality(1) holds HenceTheorem 3 holds well

Acknowledgment

Penumurthy Parvateesam Murthy is thankful to the Uni-versity Grants Commission New Delhi India for financialassistance throughMajor Reserch Project File no 42-322013(SR)

References

[1] Y I Alber and S Guerre-Delabriere ldquoPrinciple of weaklycontractive maps in Hilbert spacesrdquo in New Results in OperatorTheory and its Applications I Gohberg and Y Lybich Eds vol98 of Operator Theory Advances and Applications pp 7ndash22Birkhauser Basel Switzerland 1997

[2] B E Rhoades ldquoSome theorems on weakly contractive mapsrdquoNonlinear Analysis Theory Methods amp Applications A Theoryand Methods vol 47 no 4 pp 2683ndash2693 2001

[3] B S Choudhury and P N Dutta ldquoA unified fixed point resultin metric spaces involving a two variable functionrdquo Filomat no14 pp 43ndash48 2000

[4] P N Dutta and B S Choudhury ldquoA generalisation of con-traction principle in metric spacesrdquo Fixed Point Theory andApplications vol 2008 Article ID 406368 8 pages 2008

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of

Page 6: Research Article Weak Contraction Condition …downloads.hindawi.com/journals/jmath/2013/967045.pdfDepartment of Pure and Applied Mathematics, Guru Ghasidas Vishwavidyalaya, Bilaspur,

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical Problems in Engineering

Hindawi Publishing Corporationhttpwwwhindawicom

Differential EquationsInternational Journal of

Volume 2014

Applied MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Mathematical PhysicsAdvances in

Complex AnalysisJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

OptimizationJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Operations ResearchAdvances in

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Function Spaces

Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of Mathematics and Mathematical Sciences

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Algebra

Discrete Dynamics in Nature and Society

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Decision SciencesAdvances in

Discrete MathematicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom

Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Stochastic AnalysisInternational Journal of