evnrev01

Upload: mahesh007

Post on 09-Apr-2018

215 views

Category:

Documents


0 download

TRANSCRIPT

  • 8/8/2019 EVNREV01

    1/5

    Review Exercises for Chapter 1

    2. Precalculus.L 9 12 3 12 8.25

    4.

    limx0

    fx 0.2

    1

    0.5

    1

    0.5

    x 0.1 0.01 0.001 0.001 0.01 0.1

    0.358 0.354 0.354 0.354 0.353 0.349fx

    6. (a) does not exist.limx2

    gxgx 3x

    x 2(b) lim

    x0gx 0

    8.

    Let be given. We need

    x 9 < x 3

    x

    3<

    x

    3

    x

    3<

    x

    3

    > 0

    limx9

    x 9 3. Assuming you can choose

    Hence, for you have

    fx L <

    x 3 <

    x 9

    < 5 0limx5

    9 9. 12. limy4

    3y 1 34 1 9

    14. limt3

    t2 9

    t 3

    limt3t

    3

    6 16.

    limx0

    1

    4 x 2

    1

    4

    limx0

    4 x 2

    x

    limx0

    4 x 2

    x4 x 2

    4 x 2

    18.

    lims0

    11 s 1

    s11 s 1 lim

    s0

    1

    1 s11 s 1

    1

    2

    lims0

    11 s 1

    s lim

    s011 s 1s

    11 s 111 s 1

    20.

    4

    12

    1

    3

    limx2

    x 2

    x2 2x 4

    limx2

    x2 4

    x3

    8

    limx2

    x 2x 2

    x 2x2

    2x 4

    22. limx

    4

    4x

    tanx

    44

    1

    324 Chapter 1 Limits and Their Properties

  • 8/8/2019 EVNREV01

    2/5

    24.

    0 01 0

    limx0

    cos x 1x limx0 sin sin x

    x

    limx0

    cos x 1

    x lim

    x0coscos x sin sin x 1

    x

    26. limxc

    fx 2gx 34 2

    23

    712

    28.

    (a)

    Actual limit is

    (c)

    1

    3

    limx1

    1

    1 3x 3x2

    limx1

    1 x

    x 11 3x 3x2

    limx1

    1 3

    xx 1 lim

    x1 1 3

    xx 1 1 3

    x

    3

    x

    2

    1 3x 3x2

    13 .limx1

    1 3x

    x 1 0.333

    fx 1 3x

    x 1

    (b)

    3

    3

    3

    2

    x 1.1 1.01 1.001 1.0001

    0.33330.33320.33220.3228fx

    30.

    When the velocity is approximately

    limt6.39

    4.96.39 6.39 62.6 msec.

    limta

    sa st

    a t lim

    ta4.9a t

    t 6.39,

    st 0 4.9t2 200 0 t2 40.816 t 6.39 sec

    32. does not exist. The graph jumps from 2 to 3

    atx 4.

    limx4

    x 1 34. limx1

    gx 1 1 2.

    36. lims2

    fs 2 38.

    Removable discontinuity at

    Continuous on , 1 1,x 1

    limx1

    3x 2 5 0

    limx1

    fx limx1

    3x2

    x 2x 1

    fx 3x2 x 2x 1

    ,

    0,

    x 1

    x 1

    Review Exercises for Chapter 1 325

  • 8/8/2019 EVNREV01

    3/5

    40.

    Nonremovable discontinuity at

    Continuous on , 2 2,

    x 2

    limx2

    2x 3 1

    limx2

    5 x 3

    fx 5 x,2x 3,x 2

    x > 242.

    Domain:

    Nonremovable discontinuity at

    Continuous on ,1 0,x 0

    ,1, 0,

    limx0

    1 1x

    fx x 1x 1 1

    x

    44.

    Removable discontinuity at

    Continuous on , 1 1,x 1

    limx1

    x 1

    2x 1

    1

    2

    fx x 1

    2x 246.

    Nonremovable discontinuities when

    Continuous on

    for all integers n.

    2n 14 ,2n 1

    4

    x 2n 1

    4

    fx tan 2x

    48.

    Find b and c so that and

    Consequently we get

    Solving simultaneously, b 3 and c 4.

    1 b c 2 and 9 3b c 4.

    limx3

    x2 bx c 4.limx1

    x2 bx c 2

    limx3

    x 1 4

    limx1

    x 1 2

    50.

    Chas a nonremovable discontinuity at each integer.

    0

    0

    5

    30

    9.80 2.50x 1

    C 9.80 2.50x 1, x > 0

    54.

    Vertical asymptotes at andx 2x 2

    hx 4x

    4 x256.

    Vertical asymptote at every integer k

    fx csc x

    58. limx12

    x

    2x 1 60. lim

    x1

    x 1

    x4 1 lim

    x1

    1

    x2 1x 1

    1

    4

    62. limx1

    x2 2x 1

    x 1 64. lim

    x2

    13x2 4

    52.

    (a) Domain:

    (b)

    (c) limx1

    fx 0

    limx0

    fx 0

    , 0 1,

    fx x 1x

    68. limx0

    cos2x

    x 66. lim

    x0

    secx

    x

    326 Chapter 1 Limits and Their Properties

  • 8/8/2019 EVNREV01

    4/5

    Problem Solving for Chapter 1

    2. (a)

    (b)

    (c) limx0

    ax limx0

    x 0

    ax Area PBO

    Area PAO

    x22x2

    x

    Area PBO 1

    2bh

    1

    21y

    y

    2

    x2

    2

    AreaPAO 1

    2bh

    1

    21x

    x

    2

    x 4 2 1 0.1 0.01

    Area 2 1

    Area 8 2

    4 2 1 1100110ax

    120,000120012PBO

    120012012PAO

    70.

    (a)

    (b) Yes, define

    .

    Now is continuous atx 0.fx

    fx tan 2x

    x,

    2,

    x 0

    x 0

    limx0

    tan 2x

    x 2

    fx tan 2x

    x

    x 0.1 0.01 0.001 0.001 0.01 0.1

    2.0271 2.0003 2.0000 2.0000 2.0003 2.0271fx

    4. (a)

    (b) Tangent line:

    (c) Let

    (d)

    This is the slope of the tangent line at P.

    limx3

    3 x

    25 x2 4

    6

    4 4

    3

    4

    limx3

    3 x3 x

    x 325 x2 4

    limx3

    25 x2 16

    x 325 x2 4

    limx3

    mx limx3

    25 x2 4

    x 325 x2 4

    25 x2 4

    mx 25 x2 4

    x 3

    Q x,y x,25 x2

    y 3

    4x

    25

    4

    y 4 3

    4x 3Slope

    3

    4

    Slope 4 0

    3 0

    4

    3

    6.

    Letting simplifies the numerator.

    Thus,

    Setting you obtain

    Thus, and b 6.a 3

    b 6.b

    3 33,

    limx0

    b

    3 bx 3.

    limx0

    3 bx 3

    x lim

    x0

    bx

    x3 bx 3

    a 3

    a bx 3

    xa bx 3

    a bx 3

    xa bx 3

    xa bx 3

    a bx 38.

    Thus,

    a 1, 2

    a 2a 1 0

    a2 a 2 0

    a2 2 a

    because limx0

    tanx

    x 1lim

    x0fx lim

    x0

    ax

    tanx a

    limx0

    fx limx0

    a2 2 a2 2

    Problem Solving for Chapter 1 327

  • 8/8/2019 EVNREV01

    5/5

    12. (a)

    Let

    (b)

    Let

    (c)

    Let

    Since this is smaller than the escape velocity for earth,

    the mass is less.

    v06.99 2.64 misec.

    limv0

    r10,600

    6.99 v02

    r10,600

    v2 v02 6.99

    v02.17 misec 1.47 misec.

    limv0

    r1920

    2.17 v02

    r1920

    v2 v02 2.17

    1920

    r v2 v

    02 2.17

    v2 1920

    r v

    02 2.17

    v048 43 feetsec.

    limv0

    r192,000

    48 v02

    r192,000

    v v02 48

    192,000

    r v2 v

    02 48

    v2 192,000

    r v

    0

    2 48

    10.

    11

    1

    2

    3

    2

    1

    y

    x

    (a)

    f1 1 1

    f3 13 0

    f14 4 4 (b)

    limx0

    fx

    limx0

    fx

    limx1

    fx 0

    limx1

    fx 1 (c) fis continuous for allreal numbers except

    x 0, 1, 12,

    13, . . .

    14. Let and let be given. There exists

    such that if then

    Let Then for

    you have

    As a counterexample, let

    Then

    but limx0

    fax limx0

    f0 2.

    limx0

    fx 1 L,

    fx

    1

    2

    x 0

    x 0.

    fax L < .ax < 1

    x 0 > 0a 0

    328 Chapter 1 Limits and Their Properties