
Rushi J. answered 05/01/19
Experienced Tutor and Actuary with a Degree in Math and Economics
by f+g i'm assuming you mean, f(x) + g(x). So that would be x2 + 2x -2 + (2/(x+3)) = ([(x2 + 2x - 2)*(x+3)] + [2])/ (x+3) = (x3+2x2-2x +3x2 + 6x - 6 + 2)/(x+3) = (x3 + 5x2 + 4x - 4)/(x+3)
fg = f(g(x)) = (2/(x+3))^2 + 2(2/(x+3)) - 2 ... it's a little difficult to type out the full response, but just evaluate. We're substituting g(x) in for x in the f(x) function. Let me know if you need clarification.