Yuanmin O. answered 08/31/20
Precalculus tutor for 1 year; Masters in Structural Engineering
From the question, we have f(x) = x^2 + 2.
If the question is asking f(a+h), it means plugging x = a+h into the equation (wherever you find x, just replace it with (a+h)
Therefore, f(a+h) + f(a) = (a+h)^2 + 2 - ( a^2 + 2) = a^2 + 2ah + h^2 + 2 - a^2 - 2 = h^2 + 2ah