Diketahui f(x) = 2x-3 (gof) (x) = 4x^2-16x+8. Tentukan rumus fungsi g^-1 (x)

fungsi invers
f(x) = 2x-3
gof(x)= 4x² -16x + 8
g(2x-3) = 4x²-16x + 8
g(x) = 4 [(x+3)/2]² - 16 [(x+3)/2 ] + 8
g(x)= (x+3)² - 8(x+3) + 8
g(x)= (x²+6x+9) -8x - 24 + 8
g(x)= x²+6x+9 -8x -16
g(x)= x² -2x - 7
g⁻¹(x²-2x-7)= x
.
x²-2x-7 = y
x²-2x = y+7
(x-1)² = y+7+1 = y+8
x- 1 = √(y+8)
x= 1 +√(y+8)

g⁻¹(x)= 1 + √(x+8)