3.Diketahui f(x)=x²+5x-8 dan g(x)=x-3. Tentukan nilai a jika (fog)(a)=6 4.Diketahui f(x)=x+3 , g(x)=2x² dan h(x)=3x-1. Tentukan a jika (fog)(a)=(hog)(a)

3)

(f₀g)(x) = f(g(x))
=(x-3)² + 5(x-3) -8
=x²-6x+9 + 5x-15 -8
=x² -6x+5x+9-15-8
=x²-x-14

=> (f₀g)(a) = 6
= a²-a-14 = 6
= a²-a-14-6=0
= a²-a-20=0
= (a+4)(a-5)=0

>> a+4=0
a=-4

>> a-5=0
a= 5


semoga membantu :)

3) f(x) = x² + 5x - 8 ,,,,,,,,,,, g(x) = x - 3 => g(a) = a - 3
(f o g)(a) = 6
f(g(a)) = 6
[g(a)]² + 5 g(a) - 8 = 6
[g(a)]² + 5 g(a) - 14 = 0
(g(a) + 7) (g(a) - 2) = 0
((a - 3) + 7) ((a - 3) - 2) = 0
(a + 4) (a - 5) = 0
a = -4 atau a = 5

4) f(x) = x + 3, g(x) = 2x², h(x) = 3x - 1
(f o g)(a) = (h o g)(a)
f(g(a)) = h(g(a))
g(a) + 3 = 3(g(a)) - 1
2a² + 3 = 3(2a²) - 1
2a² + 3 = 6a² - 1
-4a² = -4
a² = 1
a = ± 1
a = 1 atau a = -1