If f(5)=3 and f'(5)=-2, find the derivative of x^2f(x) at x=5.

Question

A. 0
B. -18
C. -12
D. -20
E. -80

I got D

Answer 1

d/dx (x^2 f(x)) = 2xf(x) + x^2 f'(x)
= 2*5*3 + 25(-2)
= -20

you are correct