Question

2x^2+x-1
Помогите решить

Answer 1

$2 {x}^{2} + x - 1 = 0$

D=

${1}^{2} - 4 \times 2 \times ( - 1) = 9 = {3}^{2}$

$x = \frac{ - 1 - 3}{4} = - 1$

$x = \frac{ - 1 + 3}{4} = 0.5$

Answer 2

2х² + х - 1 = 0

D = 1 - 4 × 2 × (-1) = 1 + 8 = 9 > 0. 3.

х1 = ( -1 + 3 ) / 4 = 2/4 = 0,5.

х2 = ( -1 - 3 ) / 4 = -4/4 = -1.

Ответ : -1 ; 0,5.

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