Question

X ao quadrado +x-2=0?

Answer 1

x^2 + x - 2 = 0
x = - 1 +- 3/2
x' = 1
x" = - 2

S = { 1 ; - 2 }

Answer 2

$x ^{2} + x - 2 = 0 \\ Discriminante = b^{2} - 4.a.c = 1^{2} - 4. 1. (-2) = 9 \\ x = \frac{1 + / - 3}{2.1} = \left \{ {{ x_{1}=2} \atop { x_{2}=-1}} \right.}}$