# Question #d4c38

Dec 12, 2017

$\ln \frac{x}{\ln} \left(7\right) = {\ln}_{7} x$

#### Explanation:

If function f(x) has inverse g(x), then f(g(x)) = x.

${\ln}_{7} \left({7}^{x}\right) = x$. By the change of base rule, this transforms to $\ln \frac{x}{\ln} \left(7\right)$

These exponentiation ones can be tough, so be careful! I messed this one up my first and second tries!

GOOD LUCK