Suatu fungsi kuadrat f(x) diketahui mempunyai nilai maksimum 5 dan nilai f(2)=f(4)=0 fungsi kuadrat disebut?

f(x) = a(x - 2)(x - 4)
f(x) = ax^2 - 6ax + 8

x = -b/2a
x = -(-6a)/2a
x = 3


f(3) = 5
a(3 - 2)(3 - 4) = 5
a(1)(-1) = 5
a = -5

f(x) = -5x^2 + 30x + 8