tolong bantu yaa, soalnya ulangan ku di ilangin guru ku

f(x) = 4x -6
gof(x)= 2x² - 5x
g{f(x)}= 2x² - 5x
g(4x-6)= 2x² - 5x

a) g(2) = ...
4x-6 = 2
4x = 8
x= 2
g(2) = 2(2)² - 5(2)
g(2)= 8-10
g(2)= -2


b) g(4x-6) = 2x²- 5x
4x - 6 =y
x =( y +6)/4
g(x) = 2{(x+6)/4}² - 5{(x+6)/4}
g(x)= 2/16 (x+6)² - 5/4 ( x+6)
g(x)= 1/8 ( x²+12x + 36) -5/4 (x +6)
g(x) = 1/8 ( x²+ 12x + 36 - 10x - 60)
g(x) = 1/8 (x² + 2x - 24)
g(x)= 1/8 x² + 1/4 x - 3

fog(x)= f{g(x)}= 4 .g(x) - 6
fog(x) = 4 {1/8x² + 1/4 x - 3
fog(x)= 1/2 x² + x - 3/4

c . (fog)⁻¹(x) =
1/2 x² + x - 3/4 = y
x² + 2x - 3/2 = 2y
x²+ 2x = 2y + 3/2
(x + 1)² = (2y + 3/2 + 1
x+ 1 = √{1/4(8y + 6+ 4)}
x = 1/2 √(8y+10)  -1
(fog)⁻¹(x)= ¹/₂ √(8x+10)  - 1

d. (fog)⁻¹(2)= ¹/₂ √(16 +10)  -1
(fog)⁻¹(2)= ¹/₂√26  - 1