# Help me typeset math formulas!

I want to type these but i just don't know how to do it. Here are the pictures:

Please give me the code to each one of them. Thank you all in advance.

• What don't you know how to do in these formulæ? – Bernard Apr 19 at 20:43
• Are you familiar with TeX's math modes -- inline math mode and display math mode? – Mico Apr 19 at 20:43

Here is a simple code for the other two formulæ. The amsmath package defines 5 matrix environments,with different delimiters. The mathtools package is an extension of the former, which defines starred variants of these matrix environment, which add the possibility of choosing the alignment of all columns via an optional argument – the default is c (centred, as in amsmath), but you also can have right or left-aligned.

\documentclass{article}
\usepackage{mathtools, amssymb}

\begin{document}

$\begin{Bmatrix*}[l] G\in V_{\tau}(x) \Rightarrow V_{\tau}(x) \neq\varnothing \\ \forall v \in V_{\tau}(x) \Rightarrow x \in v \end{Bmatrix*}$%

$\begin{Bmatrix*}[l] x\in G_1\cap G_2 \\ G_1,G_2 \in \tau_v \end{Bmatrix*} \Rightarrow \begin{Bmatrix*}[l] x \in G_1\, / \,G_1 \in \tau_v\\ x \in G_2\, / \,G_2 \in \tau_v \end{Bmatrix*}$%

\end{document}


Edit: The first formula is easily typed with the rcases environment, from mathtools:

$\begin{rcases} \exists G_1 \in\tau \,/\, x \in G_1\subset v_1 \\ v_1\subset v_2 \end{rcases} \Rightarrow x \in G_1 \subset v_2$%


• Thank you so much. – Tarek Acila Apr 19 at 23:00
• You're welcome. I suggest you take a look at the documentations of amsmath and mathtools to begin with, and also to read a tutorial on typing mathematics, such as Herbert Voß’ Math mode. – Bernard Apr 19 at 23:11
• @Bernard Oh, nice! I didn't know about rcases. I take it its other functionality (e.g. use of &) is identical to that of cases? – steve Apr 20 at 14:32
• Yes. You also have rcases* (after &, you're in text mode) and drcases(*) all maths inside are in \displaystyle., and if course dcases(*) with the brace on the left. – Bernard Apr 20 at 14:36
\documentclass{article}

\usepackage{amsmath}

\begin{document}

$\left. % https://tex.stackexchange.com/questions/298837/right-curly-brace-at-the-end-of-an-equation \begin{array}{l} \exists G_1 \in \tau \ / \ x\in G_1\subset \nu_1 \\ \nu_1 \subset \nu_2 \end{array} \right\} \implies x\in G_1\subset\nu_2$

\end{document}


The other ones should be pretty similar. See also How to write an m⨉n matrix in LaTeX?

($ and $ start and end a centered math environment; \left and \right automatically size the delimiters (e.g. parentheses, brackets, etc.) that come after them (. just means no delimiter, but is needed because every \left or \right needs its closing \right / opening \left). The \ add a space before and after the /, which is just the usual slash. \\ adds a line break. The backslashes before the other words assign them special meanings, e.g. particular symbols or environments.)