f(x)=4x-2/x-5 g(x)=x+3 fog-¹(5) adalah?

f(g(x)) = (4(x+3)-2)/(x+3)-5
f(g(x)) = (4x +10)/(x-2)
y = (4x+10)/(x-2)
xy - 2y = 4x+10
xy - 4x = 2y +10
x (y-4) = 2y+10
x = (2y+10)/(y-4)
fog^-1(x) = (2x+10)/(x-4)
fog^-1(5) = (2(5)+10)/((5)-4)
fog^-1(5) = 20/1 = 20

Fungsi invers

f(x) = (4x -2)/(x- 5)(
g(x) =  x+3  ---> g⁻¹ (x+3) = x
g⁻¹(5)= ..
x+3 = 5 --> x = 5-3 = 2
g⁻¹(5) = 2

fog⁻¹ (5) = f { g⁻¹(5)} = f (2)

f0g⁻¹ (5) = { 4(2) - 2} / {2-5} = (8-2)/(-3)
fog⁻¹ (5)= 6/-3 = - 2