Question

O assunto é função quadrática
F(x) = -8x²-8x-2
a= -8 b= -8 c= -2

Answer 1

$\mathrm{f(x)=-8x^2-8x-2}\\\\ \textrm{Para encontrarmos as ra\'izes da fun\c{c}\~ao, igualaremos}\\ \textrm{f(x) a zero e utilizaremos a f\'ormula quadr\'atica:}\\\\ \mathrm{0=-8x^2-8x-2\ \to\ 0=-4x^2-4x-1}\\ \mathrm{Coeficientes\ \to\ a=-4\ \| \ b=-4\ \| \ c=-1}\\\\ \mathrm{x=\cfrac{-b\pm\sqrt{\Delta}}{2a}\ \to\ \Delta=b^2-4ac}\\\\ \mathrm{\Delta=(-4)^2-4.(-4).(-1)=16-16=0}\\\\ \mathrm{x=\cfrac{-(-4)\pm\sqrt{0}}{2.(-4)}=\cfrac{4\pm0}{-8}=-\cfrac{1}{2}}\\\\ \textrm{Resposta}\ \to\ \mathbf{x=-\cfrac{1}{2}}$