Question

Resolva -x² + 2x - 1 = 0

Answer 1

Utilize a fórmula de Bháskara:

$-x^2 + 2x - 1 = 0 \\ \\ a = -1, \, \, b = 2, \, \, c = -1 \\ \\\Delta = b^2 - 4.a.c \\ \Delta = 2^2 - 4.(-1).(-1) \\ \Delta = 4 - 4 = 0 \\ \\x = \frac{-b\pm\sqrt{\Delta}}{2a} \\ \\ x = \frac{-2\pm\sqrt{0}}{2.(-1)} \\ \\x = \frac{-2}{-2} = 1$

A raiz da equação é 1.