# Strange quirk with Latex

1. Jul 11, 2008

### kazimir82

Check this formula:

$$\sin(x) \] \cos(x)$$

The \] there (click formula for source) seems to cause some strange indenting for sin(x). Is this a bug in the Latex formula generator?

2. Jul 11, 2008

### cristo

Staff Emeritus
I have no idea. What are you trying to use the \] for? In normal latex this ends the equation environment, but I don't think it is enabled in our forum latex.

3. Jul 11, 2008

### kazimir82

Not using the \] for any particular reason here, I discovered this by accident. Just wondering how this can happen. I'd say Latex should either display the bracket (just like \} displays a curly bracket) or display nothing at all (like anything unknown with a backslash in front of it).

Or does the \] have some undocumented function?

4. Jul 25, 2008

### Ben Niehoff

I'm writing a Latex solution for my own website, and the way mine works is that it takes the user's formula, sticks it in a skeleton .tex document inside $and$ tags, and then processes that file to produce the image.

My guess is that Physics Forums' Latex engine works in a similar fashion. In that case, typing a '\]' in your formula will cause the skeleton .tex file to look like this:

Code (Text):
\preamble
$\sin x$ \cos x \]
\postamble
So, as you see, the '\]' you typed ended the displaymath environment, causing the '\cos x' to be evaluated in a text environment. Ordinarily, displaymath is indented relative to the surrounding text. This is what happened; your 'sin x' is indented, and 'cos x' begins a new paragraph in the text environment.

5. Jul 26, 2008

### n_bourbaki

That isn't quite what is happening (though I don't know what is) since the cos is displayed in mathrm font and the x is in the math font. Perhaps the engine is guessing that this ought to be in a math environment?