Text Formatting ⇒ Write Limits below the Union of Sets Symbol

[avkuvalekar]

Hi,

I am an absolute noob in LaTeX. Any help would be immensely appreciated.
I wish to write the following -

Code: Select all

A = \cup_{x \in B) O_x

O_x are sets with a subscript x. So, set A is a union of all such sets corresponding to each x in B. I want the x \in B to appear under union symbol and not as a subscript. I am sure there will be a way to do this. Any idea how?

Thanks.

[frabjous]

I think it's normal to use \bigcup for that, rather than \cup. \bigcup is the kind of operator where the subscript will be written underneath in displayed math.

If you really want to write subscript underneath regular \cup, you could use the \mathop command, which makes its argument behave as a big operator.

Compare these two:

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\documentclass{article}
\begin{document}

\[ A = \bigcup_{x \in B} O_x \]

\[ A = \mathop{\cup}_{x \in B} O_x \]

\end{document}

[dkrulewich]

This was a handy suggestion. I found it also works, for example, with integration:
\[ A = \mathop{\int}_0^\infty x \,dx\].

Although, I'm not sure if I like the way it looks.