Derivative Help

[whytehaze]

1.Find the derivatives of the following functions:
a. f(x)= (cos x/x^2)
b. (cos x)^3
c. x sin(x^2)

2. Let f(x)=(3x^4)-(4x^3)+(2)
a. Find all the critical points of f(x), Give both cordinates of each.
b. classify each critical point as a local maximum, local minimum, or neither one.

 

[royhaas]

Use the chain rule for 1). Set the derivative equal to zero and solve for 2).