Question

Jika garis 2x+y-a=0 menyinggung parabola y=x kuadrat-2x+2, maka nilai a=

Answer 1

2x + y - a = 0
y = -2x + a

y = x² - 2x + 2

y = y
x² - 2x + 2 = -2x + a = 0
x² + 2 - a = 0
syarat menyinggung D = 0
b² - 4ac =0
0² - 4.1.(2 - a) = 0
-8 + 4a = 0
4a = 8
a = 2