Question

Let g(x) = 2x and h(x) = x^2 + 4. Find the value. (hog)(-5)

Answer 1

(h o g) (-5) means the composition of the two functions, or h [ (g(-5) ].

This is, you first calculate g(-5) and then h [ g (-5) ].

So, g ( -5) = 2 * ( - 5) = - 10

And h (-10) = (-10)^2 + 4 = 100 + 4 = 104.

In this kind of problems it is important that you keep the order of the functions: first you use the inner function, which in this case is g(x).