Q.Titik puncak fungsi kuadrat〖2x〗^2 + 8x + 3
Jawab:
fungsi kuadrat
y= 2x² + 8x + 3
xp= – b/2a = -8/2(2)
xp= -8/4
xp= – 2
substitusi x = – 2 ,ke y= 2x² + 8x + 3
yp = 2(-2)² + 8(-2) + 3
yp = 8 – 16 + 3
yp= - 5
titk puncak P(xp,yp)= (-2, 5)
caralain
y= 2x² + 8x + 3
y= 2(x² +4x) + 3
y = 2(x + 2)² – 5 ⇔ y = a(x -xp)²+ yp
xp= -2 , yp= – 5
P(-2, 5)