Question

F(x) = ax kuadrat + 4x + 3a mempunyai nilai maksimum = -11, maka a kuadrat - a =.. ..

Answer 1

Maksimum = -11
D/ -4a = - 11
(4^2) - 4(a)(3a) = 44 a
16 - 12 a^2 = 44a
12a^2 + 44a - 16= 0
3a^2 +11 a - 4 = 0
(3a -1)(a+4)= 0
a = 1/3 --> a^2 - a = 1/9 - 1/3 = - 2/9
a = -4 --> a^2 - a = 16 + 4 = 20