3. Let f(x) = 5x"- 4x and g(x) = x - x + 3. Find (f + g)(x), (f - g)(x). (fg)(x), and (x). Give the domain of each (f+ g)(x) (Simplify your answer.) (f - g)(x) = (Simplify your answer.) (fg)(x) = (Simplify your answer.) (Simplify your answer ) The domain of (f + 9)(x) is (Type your answer in interval notation ) The domain of (f - g)(x) is (Type your answer in interval notation ) The domain of (fg)(x) is (Type your answer in interval notation The domain of -(X) is 9 (Type your answer in interval notation