Помогите с алгеброй, ради христа(

1.
а)
f'(x) = 12x³ - 6x² + 4
f'(-2) = 96 - 24 + 4 = 76

б)
f'(x) = 12x³ - 7x
f'(3) = 324 -21 = 303

в)
f'(x) = 6x² - x⁴ + 10*(x^17)
f'(-1) = 6 - 1 - 10 = -5

2.
a)
f'(x) = 18x² - 8x = 2x(9x-4)
f'(x) = 0 <=> x = 0 x = 4/9
x > 4/9 : f'x) > 0
0 < x < 4/9 : f'x) < 0
0 < x : f'x) > 0

б)
f'(x) = 3x² - 18x + 15
x² - 6x + 5 = 0
d = 36 -20 = 16
f'(x) = 0 <=> x1,2 = (6 ± 4 ) / 2 = 5; 1
x > 5: f'x) > 0
1 < x < 5: f'x) < 0
x < 1: f'x) > 0

в)
f'(x) = 3x³ - 4x = x (3x² - 4)
f'(x) = 0 <=> x = 0 x = ± 2/√3
x > 2/√3: f'x) > 0
0 < x < 2/√3: f'x) < 0
-2/√3 < x < 0: f'x) > 0
x<-2/√3 : f'x) < 0
График: www.wolframalpha.com/input?i=plot+3x³+-+4x

3.
f(xₒ) = f(-3) = -108 - 27 - 5 = -140
f'(x) = 12x² - 6x
f'(xₒ) = 108 + 18 = 126
y = f(xₒ) + f'(xₒ)(x-xₒ) = -140 + 126(x + 3)