Calculus problem

Question

f(x) = 4x^5/4 + 2x^3/2 + x

(a) f’(1)

(b) f’(81)

Answer 1

Use the power rule to find f '(x).

f '(x) = (5/4)*4x^{5/4 - 1} + (3/2)*2x^{3/2 - 1} + 1

f '(x) = 5x^1/4 + 3x^1/2 + 1

Next plug in 1 and 81 for x