What is the derivative of:

Question

a) cos(3x)
b) π/x

I did (a) just by following chain rule:
-sin(3x)*3
so it's -3sin(3x)

Is that correct?

I'm not completely sure how to do (b). Would it just be like the derivative of 1/x? That's -1/(x^2), would it be -π/(x^2) ?

Answer 1

Both of your answers are correct. Nice job!