Find the derivatives of the following functions :
i.) f(x) = x^3
ii.) f(x) = 1/x
iii.) f(x) = x^2 + 3x + 2
i.) f'(x) = 3x^2
ii.) f'(x) = -1/x^2
iii.) f'(x) = 2x + 3
i.) f(x) = x^3
ii.) f(x) = 1/x
iii.) f(x) = x^2 + 3x + 2
ii.) f'(x) = -1/x^2
iii.) f'(x) = 2x + 3