Question

дана функция f=-5x^4+4x^2+15. Надите f′(4), f′(-1/3)

Answer 1

$f(x)=-5x^4+4x^2+15 \ f'(x)=-20x^3+8x \ f'(4)=-20*4^3+8*4=-1280+32=-1248 \ f'(- frac{1}{3} )=-20*(- frac{1}{3} )^3+8*(- frac{1}{3} )= frac{20}{27}- frac{72}{27} = -frac{52}{27}$