Question

given the function f(x)= x^2 + 3x + 5 find f(x+h)

Answer 1

Recall that with function evaluation you simply replace the x's on the right with whatever is in the parenthesis. So, for instance

$$
f(4) = 4^{2} + 3(4) + 5 = 33
$$

In the above example all the x's got replaced with 4 and so for f(x+h) it is the same thing. All you need to do is replace all the x's on the right with x+h.