Math & Science ⇒ Limits

[kwokowok]

Hi I want to make the document look like:
limit f(x)
= limit (x+2)/(x+1)
=(3)+2}{(3)+1
= 5/4
However, I am unsure how to do this. I've added the relevant code

Code: Select all

\[ \lim_{x\to 3} f(x) \] 
=\[ \lim_{x\to 3} \dfrac{x+2}{x+1} \]
=\dfrac{(3)+2}{(3)+1}\\ 
=\dfrac{5}{4}

[Ijon Tichy]

Please always try to post a minimal working example instead of code snippets. Despite the online compiler has a build in auto-completion, the automatically added code often fails and not seldom other code of the questioner is part of the real problem.

Code: Select all

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\begin{align*}
\lim_{x\to 3} f(x) & \\
& = \lim_{x\to 3} \dfrac{x+2}{x+1} \\
& =\dfrac{(3)+2}{(3)+1}\\ 
& =\dfrac{5}{4}
\end{align*}
or maybe
\begin{align*}
\lim_{x\to 3} f(x) & = \lim_{x\to 3} \dfrac{x+2}{x+1} \\
     & =\dfrac{(3)+2}{(3)+1}\\ 
     & =\dfrac{5}{4}
\end{align*}

\end{document}

See the amsmath user guide for more information about align* and alternatives.