Answer
$a^2+2ah+h^2-3a-3h$
Work Step by Step
Replacing $x$ with $a+h$ in the given function, $
f(x)=x^2-3x
$, then $f(a+h)$ is equal to
\begin{array}{l}
(a+h)^2-3(a+h)
\\\\=
a^2+2ah+h^2-3a-3h
.\end{array}
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.