Question

x ao quadrado +2x-1=0 me ajudem preciso para agora galera

Answer 1

x² +2x-1=0

a=1

b=2

c=-1

Δ=b²-4ac

Δ=2²-4(1)(-1)

Δ=4+4

Δ=8

√Δ=√8

√Δ=√2³

√Δ=2√2

$x={-b\pm\sqrt{\Delta} \over2a}={-2\pm2\sqrt{2} \over2}={\not2(-1\pm\sqrt{2} \over\not2}=-1\pm\sqrt{2} \\ \\ x'=-2+\sqrt{2} \\ \\ x"=-1-\sqrt{2}$

Answer 2

x² + 2x - 1 = 0

Δ = b²−4ac

Δ = (2)² −4⋅(1)⋅(−1)

Δ = 4 + 4

Δ = 8

$x = \dfrac{-b \pm \sqrt{\Delta}}{2 . a}\\ \\ \\ x = \dfrac{-(2) \pm \sqrt{8}}{2 . 1}\\ \\ \\ x = \dfrac{-2 \pm 2\sqrt{2}}{2}\\ \\ \\ x' = -1 - \sqrt{2}\\ \\ \\ x'' = -1 + \sqrt{2}$

S = {$-1 - \sqrt{2}, \ \ -1 + \sqrt{2}$}