How do you find the inverse of f(x) = 3 ln (x-2)?

1 Answer
Nov 25, 2015

f^(-1)(x) = e^(1/3 x ) + 2

Explanation:

1) Insert y for f(x):

y = 3 ln (x-2)

2) Switch x and y:

x = 3 ln(y - 2)

3) Divide both sides by 3:

1/3 x = ln(y - 2)

4) Exponentiate both sides to get rid of the logarithm:

e^(1/3 x ) = y - 2

5) Add 2 to both sides of the equation:

e^(1/3 x ) + 2 = y

6) Finally, insert f^(-1)(x) for y:

f^(-1)(x) = e^(1/3 x ) + 2