How do you find the inverse of #3^(2x)?

1 Answer
Dec 25, 2015

The step by step explanation and working is given below.

Explanation:

To find the inverse of function please follow the following steps.

Step 1: Swap x and y
Step 2: Solve for y.

The final answer would be the inverse function.

Our question 3^(2x)

y=3^(2x)

Step 1: Swap x and y.
x=3^(2y)

Step 2: Solve for y

log_3(x) = 2y Using If a=b^c then log_b(a) = c

1/2log_3(x) = y
y=1/2 log_3(x)
f^-1(x) =l/2log_3(x) Answer

If converting logarithm to the exponent form is not clear the following steps might help you understand how it is done.

log(x) = log(3^2y)
log(x) = 2ylog(3)
log(x)/(2log(3)) = y
1/2(log(x)/log(3)) = y using change of base rule.
1/2 log_3(x) = y
The inverse function f^-1(x) = 1/2 log_3(x)