Let F(x)= X^2+ 5 and G9x)= (x+1) / (x-1). Find (a) F-3G and (b) F(g(x))

F-3G = (x^2+5)-3(x+1)/(x-1)

= (x-2)(x^2+x+4)/(x-1)
or other massaging as you wish

F(G) = G^2+5 = [(x+1)/(x-1)]^2 + 5
= 2(3x^2-4x+3)/(x-1)^2