f(x-1) = x-4 g(x) = x/2 - 1 (g o f)^-1 (2) = ?

(gof)^-1 (2)
= (g(x-1))^-1 (2)
= ((x-1)/2-1)^-1 (2)
= (x/2 - 1/2 -1)^-1 (2)
= (x/2 - 3/2)^-1 (2)
= 1/(x/2 - 3/2) (2)
= 2/(x/2 - 3/2)
= 2 × 2/x-3
= 4/x-3

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