Question

determine as coordenadas do ponto vértice da função


b) f(x)=x²+8x-9



c) y= -x²+2×-2



d) y=2x²-3x-2​

Answer 1

Resposta:

f(x)=ax²+bx+c

vértice=(vx,vy)

vx=-b/2a

vy=-Δ/4a = -[b²-4*a*c]/4a

b) f(x)=x²+8x-9   ...a=1,b=8 e c=-9

vx=-8/2=-4

vy=-[64+36]/4 =-5/2

c) y= -x²+2×-2   ..a=-1 , b=2  e c=-2

vx=-2/(-2)=1

vy=-[4-8]/(-4) =-1

d) y=2x²-3x-2​   ...a=2  ; b=-3  e c=-2

vx=-(-3)/(2*2)=3/4

vy=-[9+16]/8=-25/8