Уравнение касательной к графику в точке x0:
y = f(x0)+f'(x0)(x-x0)
1) f(3) = 9-4 = 5
f'(x) = 2x
f'(3) = 6
y = 5+6(x-3) = 5+6x-18 = 6x-13
2) f(-4) = -4-16 = -20
f'(x) = 1-2x
f'(-4) = 1+8 = 9
y = -20+9(x+4) = -20+9x+36 = 9x+16
3) f(-1) = -1+1 = 0
f'(x) = 2x²
f'(-1) = 2
y = 0+2(x+1) = 2x+2
4) f(-1) = -2
f'(x) = -2/x²
f'(-1) = -2
y = -2-2(x+1) = -2-2x-2 = -2x-4
5) f(4) = 2
f'(x) = 1/2√x
f'(4) = 1/4
y = 2+1/4(x-4) = 2-1/4x-1 = -1/4x+1