1 . Pake matriks 1 . Pertanyaan : Nilai x dan y dari 3x - 5y = 11 2x + y = 3 ..cari nilai x dan y? 2. Diketahui fx = 5x - 1 dan Gx = X² + 3 . Tentukan FOG dan G

Matematika

Nomor 1
3x - 5y = 11 --- (×1)
2x + y = 3 ---- (×5)

3x - 5y = 11
10x + 5y = 15
__________+
13x = 26
x = 2

2x + y = 3
y = 3 - 2(2)
y = -1

x → 2
y → -1

Nomor 2
f(x) = 5x - 1
g(x) = x² - 3

(fog)(x) = f{g(x)}
............ = 5g(x) - 1
............ = 5(x² - 3) - 1
............ = 5x² - 16

(gof)(x) = g{f(x)}
............ = f(x)² - 3
............ = (5x - 1)² - 3
............ = 25x² - 10x - 2