1.5 The Algebra of Functions
Checkpoint 5
Click on the calculator icon at the right to pop up a numeric calculator. Then check our assertions about logarithms and exponentiation, using base `10`. You can use the 
(after entering `10` for `x`) and 
keys on the calculator, or you can enter everything from your keyboard.
- Select a number `y` of your choice, and raise `10` to the `y` power. Apply `log` to the result, and observe whether you get `y` back. (This check will be more interesting if your `y` is not `0` or `1` or a very large number.)
- Now select a positive number `x`, and calculate `log_10` of it. Use the resulting number as an exponent, with `10` as base, and see whether you get `x` back.
- Repeat parts (a) and (b) with several other values of `y` and `x`.