First of all, sorry for asking so many questions. I do not want answers, just a method of solving them.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

For the exponential function f(x) = ab^x, suppose f(2) = 2 and f(4) = 18.

a. Find a and b.

b. Find f^-1(54), the inverse function.

2. Relevant equations

None, really...

3. The attempt at a solution

a. f(2) = 2, meaning ab^2 = 2. f(4) = 18, meaning ab^4 = 18.

(ab^2 = 2) * 9 -> 9ab^2 = 18

ab^4 = 18

9ab^2 = ab^4

divide both sides by ab^2

9 = b^2

b = 3

a(3)^2 = 2

9a = 2

a = 2/9

b. The inverse of ab^54...

Inverse of: (2/9)(3)^54

And from here, I'm lost. Do you fifty-fourth root everything because it is the inverse?

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# Homework Help: Inverse Exponential Functions

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