8242

21

2

OR

To find 8 as a base of 2

EXPONENTIAL EQUATION

Equations involving variables in the exponents of base.

2x+1=8

Step 1 : Write both of the term as the power of same base

2x+1=8

2x+1=23

Step 2 : Equate the power and solve as linear equation

2x+1=23

x+1=3

x=3−1

x=2

EXERCISE

Find the value of x in each of the following.

1. 2x = 4

2. 4x = 64

3. 5x = 625

4. 2(x – 1) = 8

5. 42x = 64

6. 3x = 9(x – 1)

7. 3(x + 2) = 27

8. 10(x + 1) = 1

9. 5x = 125x

10. ( 12 )x = 8

11. ( 12 )x = 32

12. ( 12 ) (x + 1) = 2

13. ( 116 )x = 4

14. ( 13 )x = 81

15. 3–x = 27

16. 2(–x + 3) = 64

17. 2–x =1256

18. 2–x = 128

19. 4–x = 116

20. 3 (–x + 1) = 181