Question

how do u find the derivative of f(x) = 4x^3/4 -5x
I got f'(x)=3/x^1/4 - 5 can I combine these to get one fraction

Answer 1

\[f \prime(x) = 3/x ^{1/4}-5\]

Answer 2

so then how would I find f''(x). Do I use the quotient rule

Answer 3

Yes, you can use the quotient rule again. So \[f \prime \prime(x) = -(3/4)x^{-5/4}\]