Решить уравнения:

1) (0,8x - 2) (3x + 1) = 0;

2) 18x³ - 9x² = 0;

3) x (x + 2) (5x - 1) = 0;

4) (2x + 1) ² = (x + 2) ²;

1) (0,8x - 2) (3x + 1) = 0;

0.8 х-2=0 3 х+1=0, 3 х=-1, х=-1/3

0,8 х=2

х=2,5

2) 18x³ - 9x² = 0;

9x² (2 х-1) = 0

9x²=0 и 2 х-1=0, х=1/2

х=0

3) х (x + 2) (5x - 1) = 0

х=0 и х=-2 и х=1/5

1) (0,8x - 2) (3x + 1) = 0

0,8x-2=0 3x+1=0

0,8x=2 3x=-1

x=2,5 x=-1/3

2) 18x³ - 9x² = 0

9x² (2x-1) = 0

9x²=0 2x-1 = 0

x=0 x=1/2

3) x (x + 2) (5x - 1) = 0

x=0 x+2=0 5x-1=0

x=-2 x=1/5

4) (2x + 1) ² = (x + 2) ²

4x²+4x+1 = x²+4x+4

4x²+4x+1-x²-4x-4=0

3x²-3=0

3 (x²-1) = 0

3 (x-1) (x+1) = 0

x-1 = 0 x+1=0

x=1 x=-1