diketahui f (x)=3x-1 dan (fog)(x)=x^2+5 tentukan g (x)

f(x) = 3x - 1
fog(x) = x² + 5

maka
fog(x) = x² + 5
f(g(x)) = x² + 5
3g(x) - 1 = x² + 5
3g(x) = x² + 5 + 1
3g(x) = x² + 6
g(x) = x²/3 + 2

jawab

dengan cara lain

f(x) = 3x - 1
f ⁻¹(x) = 1/3(x +1)

g(x) = f⁻¹ o  (fog)
g(x) = 1/3 { fog(x) + 1}
g(x) = 1/3 { x² + 5 + 1}
g(x) = 1/3 {x² + 6 }
g(x) = 1/3 x²  + 2