# Missing } Inserted?

I wrote

    \begin{align}
$\lim_{x \to 2} f(x)$ &= $\lim_{x \to 2}\dfrac{2x^2-5x+2}{5x^2-7x-6}$\\
&= $\lim_{x \to 2}\dfrac{(x-2)(2x-1)}{(x-2)(5x+3)}$\\
\end{align}


But apparently I have a missing } and I cannot find it. Help?

• Welcome to TeX.SX! Remove the  characters: you're already in math mode when you start align. – egreg Jun 14 '14 at 22:40 • Oh, so I don't need the characters for the align environment? – Linda Jun 14 '14 at 22:42
• No, they are for inline math formulas, not for displays. – egreg Jun 14 '14 at 22:43

When you start a display environment, be it



\begin{equation*}

\begin{align}

\begin{align*}

\begin{gather}

\begin{gather*}


and the other display environments, you are already in math mode, so a $ character is illegal. Type $<formula>\$ only for inline math formulas.

So

\begin{align}
\lim_{x \to 2} f(x) &= \lim_{x \to 2}\dfrac{2x^2-5x+2}{5x^2-7x-6} \\
&= \lim_{x \to 2}\dfrac{(x-2)(2x-1)}{(x-2)(5x+3)}
\end{align}


Don't add \\ to the last row of a display environment. It's optional in array, but at the outer level in a display environment it would produce an unwanted blank line.