Here's a special exponential that I haven't told you about yet:

He's got a special inverse too...

This log turns up so much (biology, chemistry, geology, sound engineering and more), it's  called "the common log."  It even has its own button on your calculator!

See it?  Notice that they leave the base, 10, off?

It's because this is the most commonly used log, so the 10 is just assumed.  From now on, when you see

, it's really

.

(Just like you leave the 2 off the square root...)

Let's review the graph of

:

 

 

Now, you can graph his inverse,

:

* Remember to switch the x's and y's!