Question

Determinar as coordenadas do vértice V da parábola que representa a função f(x)= x²-2x -3.

Answer 1

$x_v=\dfrac{-b}{2a}=\dfrac{-(-2)}{2}=1$

$y_v=\dfrac{-\Delta}{4a}$

$\Delta=(-2)^2-4\cdot1\cdot(-3)=4+12=16$

$y_v=\dfrac{-16}{4}=-4$

$v(1,-4)$.