Diketahui ƒ(x) = 2x4 + 9x3 - 9x - 4 tentukanlah : a. ƒ’(x) b. ƒ”(x)

a) f'(x)=8x³+27x²-9
b) f''(x) =24x²+54x

f'(x)=(4)(2)(x)^(4-1)+(3)(9)(x)^(3-1)-9
=8x^3+27x^2-9

f"(x)=(3)(8)(x)^(3-1)+(2)(27)(x)
=24x^2+54x