Question

 Qual o zero da função f(x)=-x²-5/6 x-1/6 ?

Answer 1

I) $x^{2} - \frac{5x}{6} - \frac{1}{6} = 0 ( MMC) 6x^{2} - 5x -1 = 0 ,$
 a = 6, b = -5 e c = -1 
$II) Delta = b^{2} - 4 . a . c$
$D = (-5)^{2} - 4 . 6 . (-1) .D = 25+ 24 D = 49$

II) x = - b +$\sqrt[2]{D}$  / 2a
x' = $\frac{5+7}{2.6} = \frac{12}{12} = 1$

x'' = $\frac{5-7}{2.6} = \frac{-2}{12} = \frac{-1}{6}$