Parabola y=ax^2 + bx + c melalui titik (0,0), (2,3), (3,6). tentukanlah (a+b+c)
Jawaban Terkonfirmasi
(x,y) = (0,0)
0 = a(0)² + b(0) + c
0 = 0 + 0 + c
c = 0
(x,y) = (2,3)
3 = a(2)² + b(2) + 0
3 = 4a + 2b (persamaan 1)
(x,y) = (3,6)
6 = a(3)² + b(3) + 0
6 = 9a + 3b (persamaan 2)
eliminasi persamaan 1 dan 2
3 = 4a + 2b |×3| ==> 9 = 12a + 6b
6 = 9a + 3b |×2| ==> 12 = 18a + 6b
jadinya
12 = 18a + 6b
9 = 12a + 6b
——————– _
3 = 6a
a = 3/6 = ½
3 = 4(½) + 2b
3 = 2 + 2b
3 – 2 = 2b
1 = 2b
b = ½
a + b + c = ½ + ½ + 0 = 1