# Diagram(square)

I need help to make a diagram(square), someone can teach me how to do?

I know that I could look at the posts to see a model, but I am stopped for 7 days to edit questions

• I remember looking into making diagrams with TeX and whether these would then be properly rendered by MathJAX. My impression was it's kind of an iffy thing, and that the more beaten path here is to construct an image and upload/link it using the picture icon shown above the Your Answer box. Or were you wanting to put it in a Question? – hardmath Jan 7 '13 at 20:07
• Possible duplicate: meta.math.stackexchange.com/questions/2324/… – Julian Kuelshammer Jan 7 '13 at 20:15
• @hardmath I want put it in a question – user52188 Jan 7 '13 at 20:18

$$\begin{array}{ccc}A&\to& B\\\downarrow &\nearrow&\uparrow\\A'&\to& B'\end{array}$$

$$\begin{array}{ccc}A&\to& B\\\downarrow &\nearrow&\uparrow\\A'&\to& B'\end{array}$$

Even if you are stopped from editing questions for seven days, you can still see the MathJax code!

Right click on a math expression (for instance, that in Asaf's answer), in the context menu, select "show math as" -> "tex commands". This will bring up a pop-up window showing the MathJax expression that went into constructing that particular display.