Question

Determine a soluçao, em IR, da inequaçao do 2 grau (x - 1 )^2 + x > 3

Answer 1

(x-1)^2 + x > 3 
(x-1)(x-1) + x > 3
x^2 - x - x +1 + x > 3
x^2 + x - 2 > 0
delta = b^2 - 4ac
delta = 1^2 - 4 * 1 * (-2)
delta = 1 + 8
delta = 9
x = (-b +/- raiz de delta)/2a
x' = (-1 + 3)/2
x' = -2/2 = -1
x'' = (-1-3)/2
x'' = -4/2 = -2