Найдите f'(3) и f'(1) если : f(x)=1/x + 1/x²

Question

Найдите f'(3) и f'(1) если : f(x)=1/x + 1/x²

Answer 1

F´(x) = -1/(xˇ2)-2/(xˇ3)
f´(3) = -1/9 -2/27=-3/27-2/27=-5/27
f´(1) = -1/1 -2/1)=-1-2=-3