Soal latihan UTS tahun lalu nih. Fungsi g didefinisikan dengan rumus g(x)=2x²-7 a.hitunglah g(6) dan g(-4) b.Jika ditentukan g(a)=11,bentuklah persamaan dalam a

g(x) = 2x² - 7
a. hitung g(6) dan g(-4)
g(6) = 2(6)²-7 = 2(36)-7 = 72-7 = 65
g(-4) = 2(-4)²-7 = 2(16)-7 = 32-7 = 25

b. g(a) = 11
g(a) = 2(a)²-7
11 = 2(a)²-7
11+7 = 2(a)²
18/2 = a²
9 = a²
√9 = a
a = 3

g(x) = 2x^2 _ 7
g(6) = 2x 6^2 _7 = 72 _7 = 65
g(_4) = 2x _4^2 _7 = 32 _ 7 = 25

g(a) =11
2a^2 _ 7 = 11
2 x a^2 = 11 + 7 =18
a^2 = 18/2 = 9
a = akar 9 = 3