Question

What is the derivative of `picosx`?

Answer 1

`-pisinx`

Explanation:

Remember that `pi` is just a constant. Don't let it cloud your thoughts when trying to differentiate.

The only other thing to know for this problem is that `d/dx[cosx]=-sinx`.

Thus, the constant `pi` is kept at the front multiplied to the new derivative, so:

`d/dx[picosx]=pid/dx[cosx]=pixx-sinx=-pisinx`