Question

A parabola da funçao f(x)= -x^2 -2x -3 possui vertice no ponto das coordenadas
A>>> (-4 , -1)
B >>> (-5/2 , -1/4)
C >>> (-1 , -2)
D >>> ( -1/2 , 2

Answer 1

.$- x^{2} -2x-3=0 \\ \\ Xv=- \frac{b}{2a} = \frac{-(-2)}{2(-1)} = \frac{2}{-2} =-1 \\ \\Yv=- \frac{\Delta}{4a} = \frac{-[(-2)^2-4(-1)(-3)]}{4(-1)} = \frac{-[4-12)]}{-4} = \frac{-(-8)}{-4} = \frac{8}{-4} =-2 \\ \\ V(-1,-2)$

Letra C