Question

Решить квадратные уравнения.
1) 4x2 – x – 3 = 0
2) 5x2 + 6x + 1 = 0
3) x2 – 6x + 8 = 0
4) x2 + 5x + 6 = 0
5) x2 + 6x + 9 = 0
6) 5x2 + 2x +3 = 0
7) x2 + 7x = 0
8) x2 – 3 = 0
9) x2 + 4 = 0

Answer 1

1.

$4x^{2}- x - 3 = 0$

$x1 = - \frac{3}{4} \: \: \: \: \: \: \: \: \: \: x2 =1$

2.

$5 {x}^{2} + 6x + 1 = 0$

$x1 = - 1 \: \: \: \: \: \: \: \: \: \: \: \: \: x2 = - \frac{1}{5}$

3.

${x}^{2} - 6x + 8 = 0$

$x1 = 2 \: \: \: \: \: \: \: \: \: \: x2 = 4$

4.

${x}^{2} + 5x + 6 = 0$

$x1 = - 3 \: \: \: \: \: \: \: \: \: \: x2 = - 2$

5.

${x}^{2} + 6x + 9 = 0$

$x = - 3$

6.

$5 {x}^{2} + 2x + 3 = 0$

Нет корней

7.

${x}^{2} + 7x = 0$

$x1 = - 7 \: \: \: \: \: \: \: \: \: \: \: \: \: x2 = 0$

8.

${x}^{2} - 3 = 0$

$x1 = - \sqrt{3} \: \: \: \: \: \: \: x2 = \sqrt{3}$

9.

${x}^{2} + 4 = 0$

Нет корней