- Thread starter
- #1

#### TheBigBadBen

##### Active member

- May 12, 2013

- 84

\(\displaystyle

f(x)=\left{ \begin{array}{ccc}

1 & x \in \mathbb{Q} \\

0 & x \notin \mathbb{Q}

\end{array} \right

\)

What's going on, and how do I fix it?

- Thread starter TheBigBadBen
- Start date

- Thread starter
- #1

- May 12, 2013

- 84

\(\displaystyle

f(x)=\left{ \begin{array}{ccc}

1 & x \in \mathbb{Q} \\

0 & x \notin \mathbb{Q}

\end{array} \right

\)

What's going on, and how do I fix it?

- Admin
- #2

- Jan 26, 2012

- 4,052

There are two small things to fix and it works just fine. The first is when you want to add brackets {} using Mathjax you need to add another slash before it. So it should read "\left \{". The other thing is at the end of "\right" you need to add a period. If you do those two things this is what renders.

\(\displaystyle

f(x)=\left\{ \begin{array}{ll}

1 & x \in \mathbb{Q} \\

0 & x \notin \mathbb{Q}

\end{array} \right.\)

- Admin
- #3