Koordinat titik potong grafik fungsi kuadrat f(x) =(x+1)-8

[tex]y = 2 {(x + 1)}^{2} - 8 \\ = 2( { {x}^{2} + 2x + 1)} - 8 \\ = 2 {x}^{2} + 4x + 2 - 8 \\ = {2x}^{2} + 4x - 6[/tex]

cari tipot sb.y maka x = 0. (0,6)
[tex]y = {2.0}^{2} + 4.0 - 6 \\ = 6[/tex]

cari tipot sb.x maka y=0. (1,0) (-3,0)
[tex]0 = {2x}^{2} + 4x - 6 \\ 0 = (2x - 2)(x + 3) \\ 2x - 2 = 0 \: \: \: atau \: \: \: x + 3 = 0 \\ x = \frac{2}{2} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: x = - 3 \\ x = 1[/tex]