Jika f(x)=3x-1 dan g(x)=2x^2+2 maka tentukan (fog)(x)<(fog)(-3) dan (gof)(x)<(gof)(2)
Dik: f(x)= 3x-1 dan g(x)= 2x²+2
Dit:a). f o g (x) b). f o g (-3) c). g o f (x) d). g o f (2)
Jawab:
a) f o g (x) c) g o f (x)
= 3x-1 = 2x²+2
= 3(2x²+2)-1 = 2(3x-1)²+2
= 6x²+6-1 = 6x²-2+2
= 6x²+5 = 6x²
b) f o g (-3) d) g o f(2)
= 6x²+5 = 6x²
= 6(-3)²+5 = 6(2)²
= 6.9+5 = 6.4
= 54 = 24