Пошаговое объяснение:
1. f'(x)=-3x^2+18x+1;
f'(-1)=-3-18+1=-20
2. f'(x)=x^3-x^2+x;
f'(3)=3^3-3^2+3=21
3. 0
4.
5. 3x^2-2x-1=0
D = b2 - 4ac = (-2)2 - 4·3·(-1) = 4 + 12 = 16
x1 = (2 - √16) / 2·3 = (2 - 4)/ 6 = -2/6 = - 1/3
x2 = (2 + √16)/ 2·3 = (2 + 4)/ 6 = 6/6 = 1