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)#