Question

F(x) = -3x + 1 dan g(x) = 2x / x – 1 maka (g-1 ○ f-1)(x) = ...
A. X + 1 / x + 5
B. X + 1 / x – 5
C. X – 1 / x – 5
D. X – 1 / x + 5
E. X / x + 5

Answer 1

F(x) = -3x + 1 dan g(x) = 2x / x – 1 maka (g-1 ○ f-1)(x) 
jawab
f (x) = -3x + 1
 y    = -3x + 1 ---- x (-1)
-y    = 3x - 1
- y + 1 = 3x
-y + 1/3 = x
f⁻¹(x) = -x +1 / 3
sementara 
g(x) = 2x/x -1
  y      = 2x/x-1
xy - y = 2x 
xy -2x = y
 x ( y-2) = y
   x     = y / y-2
g⁻¹(x) = x/x-2
jawaban 
f⁻¹ o g⁻¹ = - ( x/per x-2) +1 per 3
             = (-x/-x-2) + 1/ 3