We don't need any special methods to see that

But what about the equation

We can see from the graph that there should be an answer around $x\approx 2.6$ or so. So how do we find $x$?

What we need is an inverse function! If $f$ is defined by

then the solution to

is

This is where logarithms come in, as we will see in the next example.

Use logarithms to solve the following equations, giving your answers to $3$ significant figures where necessary.