Question

Решите уравнение:
1)2х²-(2х²-5х)-(4х-2)=5
2)(у³+у)+(3-6у)-(4-5у)=-2
3)(х²-7х-11)-(5х²-13х-18)=16-4х²​

Answer 1

Ответ:

$1)2 {x}^{2} - 2 {x}^{2} + 5x - 4x + 2 = 5 \\ x + 2 = 5 \\ x = 5 - 2 \\ x = 3$

$2) {y}^{3} + y + 3 - 6y - 4 + 5y = - 2 \\ {y}^{3} - 1 = - 2 \\ {y}^{3} = - 2 + 1 \\ y = - 1$

$3) {x}^{2} - 7x - 11 - 5 {x}^{2} + 13x + 18 \\ = 16 - 4 {x}^{2} \\ - 4 {x}^{2} + 6x + 7 = 16 - 4 {x}^{2}$

$- 4 {x}^{2} + 6x + 7 - 16 + 4 {x}^{2} = 0 \\ 6x - 9 = 0 \\6 x = 0 + 9 \\ 6x = 9$

$x = 9 \div 6 \\ x = \frac{9}{6} = \frac{3}{2} = 1 \frac{1}{2} = 1.5$