I am new to latex. I need to write the following equation in latex.

I have tried following packages:-

```
\usepackage{amssymb}
\usepackage{amsmath}
L1 \cap Li \neq \Phi
```

But i constantly get error and non of the symbols gets displayed. what am i doing wrong. (i am using XeLatex as there are both English and urdu Fonts in my article)

## Best Answer

It works for me if I complete your code to create a minimal example:

Admittedly, this isn't yet

quiteright because it does not look quite like the target set of symbols.To obtain a subscript in a mathematical expression, just use

`L_{<subscript>}`

. To obtain the lowercase Greek letter, use`\phi`

rather than`\Phi`

.## EDIT

In light of Heiko Oberdiek's comment, for the final symbol, I'm not entirely clear which one you want but I suspect that Heiko may be right. In any case, here's a selection to choose from: