Suppose that the functions g and h are defined for all real numbers as follows.
g(x) = 3x + 5 h(x) = 4x
(g · h)(x) = g(x) · h(x) = (3x + 5) · (4x) = 12x2 + 20x
(g + h)(x) = g(x) + h(x) = (3x + 5) + (4x) = 7x + 5
(g - h)(x) = g(x) - h(x) = (3x + 5) - (4x) = -x + 5
---> (g - h)(3) = -3 + 5 = 2
