Question

Resolvam essa equação do 2° grau, por favor!!!

-x² + 4x - 2 = 0​

Answer 1

$\dfrac{-b\±\sqrt{b^2-4ac}}{2a}=\\\\\dfrac{-4\±\sqrt{4^2-4\cdot(-1)\cdot(-2)}}{2\cdot(-1)}=\\\\\dfrac{-4\±\sqrt{16-8}}{-2}=\\\\\dfrac{-4\±2\sqrt{2}}{-2}=$

Se +:

$\dfrac{-4+2\sqrt{2}}{-2}=\\\\2-\sqrt{2}$

Se -:

$\dfrac{-4-2\sqrt{2}}{-2}=\\\\2+\sqrt{2}$