1) (1-2x)(4x² +2x+1)=8(1-x²)(x+2)2) 3x²+9=12x-x²3)x(2x+1)=3x+44)x(x+2)=-3

Раскроем скобки и решим уравнения:

1) (1 - 2х) * (4х^2 + 2х + 1) = 8 * (1 - х^2) * (х + 2);

4х^2 + 2х + 1 - 8х^3 - 4х^2 - 2х = 8 * (х + 2 - х^3 - 2х^2);

1 - 8х^3 = 8х + 16 - 8х^3 - 16х^2;

16х^2 - 8х - 15 = 0.

D = b^2 - 4ac = 64 + 960 = 1024.

x1 = (-b + √D)/2a = (8 + 32)/32 = 40/32 = 1 1/4;

x2 = (-b - √D)/2a = (8 - 32)/32 = -24/32 = -3/3.

2) 3x^2 + 9 = 12x - x^2;

3x^2 + x^2 - 12x + 9 = 0;

4x^2 - 12x + 9 = 0.

D = 144 - 4 * 4 * 9 = 0.

x = -b/2a = 12/8 = 1 1/2.

3) x * (2x + 1) = 3x + 4;

2x^2 + x - 3x - 4 = 0;

2x^2 - 2x - 4 = 0.

D = 4 + 4 * 2 * 4 = 36.

x1 = (2 + 6)/4 = 8/4 = 2;

x2 = (2 - 6)/4 = -4/4 = -1.

4) x * (x + 2) = -3;

x^2 + 2x + 3 = 0;

D = 4 - 4 * 1 * 3 = -8.

D < 0, уравнение не имеет действительных корней.