Question 2243
22.  f[g(x)] = f(x+2) =  (x+2)^2.

23. [g•f](2)= g(f(2)) = g(2^3 + 4) = g(12) = 12+3 = 15

24. Let y = f(x)=4x+1, then 4x = y - 1, or x =(y - 1)/4.
    Exchange x,y we have y =(x - 1)/4. 
    Hence, the inverse function is g(x) = (x - 1)/4.

25. Answer : c. f(x)=x+5, g(x)=x-5
    Since f[g(x)] = g[f(x)] = x