How would I do the derivative of(adsbygoogle = window.adsbygoogle || []).push({});

f(x) = cos pi*x

I know f'(x) cos x = - sin x but what about that pi?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Derivative of f(x) = cos pi*x

**Physics Forums | Science Articles, Homework Help, Discussion**