Question

25 баллов. решите пожалуйста 5 примеров буду очень благодарен​

Answer 1

Ответ:

Пошаговое объяснение:

1. x(1/5 - 25x) = 0

x1 = 0

x2 = 1/125

2. x(3 - 2/5x) = 0

x1 = 0

x2 = 15/2 = 7,5

3. x² = 4

x1 = -2

x2 = 2

4. 5x² = 8

x² = 1,6

x1 = -√1,6

x2 = √1,6

5. D = 49 - 40 = 9

x1 = (-7 - 3)/2 = -5

x2 = (-7 + 3)/2 = -2

Answer 2

1

$\frac{1}{5} x + 25 {x}^{2} = 0 \\ x + 125 {x}^{2} = 0 \\ x \times (1 + 125x) = 0 \\ \\ x = 0 \\ 1 + 125x = 0 \\ \\ x1 = - \frac{1}{125} \\ x2 = 0$

2

$3x - \frac{2}{5} {x}^{2} = 0 \\ 15x - 2 {x}^{2} = 0 \\ x \times (15 - 2x) = 0 \\ \\ x = 0 \\ 15 - 2x = 0 \\ \\ x1 = 0 \\ x2 = \frac{15}{2} = 7.5$

3

$5 {x}^{2} = 20 \\ {x}^{2} = 4 \\ x1 = - 2 \\ x2 = 2$

4

$4 {x}^{2} = 8 - {x}^{2} \\ 4 {x}^{2} + {x}^{2} = 8 \\ 5 {x}^{2} = 8 \\ {x}^{2} = \frac{8}{5} \\ x = + - \sqrt{ \frac{8}{5} } \\ x = + - \frac{2 \sqrt{10} }{5} \\ x1 = - \frac{2 \sqrt{10} }{5} \\ x2 = \frac{2 \sqrt{10} }{5}$

5

${x}^{2} + 7x + 10 = 0 \\ {x}^{2} + 5x + 2x + 10 = 0 \\ x(x + 5) + 2(x + 5) = 0 \\ (x + 5)(x + 2) = 0 \\ \\ x + 5 = 0 \\ x + 2 = 0 \\ x1 = - 5 \\ x2 = - 2$