Question

1) Dada a função y = x? - 4x - 5, determine:
a) as raízes;
b) as coordenadas do vértice.

Answer 1

Vamos lá.

x² - 4x - 5 = 0

a = 1

b = -4

c = -5

delta

d² = 16 + 20 = 36

d = 6

as raízes

x1 = (4 + 6)/2 = 5

x2 = (4 - 6)/2 = -1

vértice

Vx = -b/2a = 4/2 = 2

Vy = -d²/4a = -36/4 = -9