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What are the values of a and b in the equation (4x^a)^b = 256/x^8

2 Answers

6 votes
b = 4 and a = -2

(4x^-2)^4
= 4^4 x^-8
= 4^4 / x^8
= 256/x^8
User Vqf
by
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3 votes

Answer:

The value of a is -2 and the value of b is 4.

Explanation:

Given expression is,


(4x^a)^b = (256)/(x^8)

Using
(ab)^m=a^m.b^n on left side,


4^b(x)^(ab)=(4^4)/(x^8) (
4^4 = 256 )

Using
a^m=(1)/(a^(-m)),


4^b(x)^(ab)=4^4 (x)^(-8)

By comparing both sides,

We get,

b = 4 and ab = -8

⇒ a = -2

Hence, the value of a is -2 and the value of b is 4.

User Darren G
by
7.2k points