Writing Math on the Forum: A Guide to LaTeX and MathJax

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If you've ever wanted to post an equation, a formula, or a bit of technical notation on the forum and had it come out looking like a jumbled mess of slashes and symbols, this guide is for you. Our forum now supports MathJax, a tool that turns plain text math code into properly typeset equations — the kind you'd see in a textbook or scientific paper.

You don't need any special software to use this. Everything happens right in the "New Topic" or "Reply" editor, using two buttons: latex and latex_para. Clicking one of these buttons wraps your cursor in a pair of tags:

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[latex][/latex]

You then type your math code between the tags, and MathJax converts it into a proper equation once the post is submitted (or shown in Preview).

Every example below follows the same pattern: a "Type:" line showing exactly what to type, followed by a "Result:" line showing the actual equation MathJax produces.

What is LaTeX, and why does it look strange?

LaTeX (pronounced "lay-tech" or "lah-tech") is a typesetting language that scientists, engineers, and mathematicians have used for decades to write equations. Instead of trying to draw a fraction or a square root with your keyboard, you describe it using a short code, and the system draws it for you.

For example, after clicking the latex button:

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[latex]x^2 + y^2 = z^2[/latex]

Result: \(x^2 + y^2 = z^2\)

It looks a little odd at first, but you only need to learn a handful of symbols to cover most everyday use.

The Two Buttons: latex vs. latex_para

latex is for inline math — a small equation that sits right in the middle of a sentence, the same size as your regular text. Use this when you want to reference a variable or a short expression without breaking up your paragraph.

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The theorem holds because [latex]a^2 + b^2 = c^2[/latex], as shown above.

Result: The theorem holds because \(a^2 + b^2 = c^2\), as shown above.

latex_para is for display math — a larger, centered equation that stands on its own line, separated from the surrounding text. This is what you want for a longer formula, a multi-line derivation, or anything you want to visually emphasize.

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[latex_para]a^2 + b^2 = c^2[/latex_para]

Result: \[a^2 + b^2 = c^2\]

Compare the two results above — the first stays tucked into the sentence, the second gets its own centered line.

Rule of thumb: if the equation is short and part of a sentence, use the latex button. If it deserves its own spotlight, use the latex_para button.

How to Actually Use the Buttons

1. Click New Topic or Reply to open the editor.
2. Place your cursor where you want the equation to go.
3. Click either the latex or latex_para button. This inserts a tag pair with your cursor positioned in the middle, ready to type.
4. Type your LaTeX code between the tags.
5. Continue writing the rest of your post as normal.
6. Before posting, use the Preview button (if available) to check that your equation renders the way you expect.

You can use the buttons as many times as you like in a single post — mix inline expressions into your sentences and drop display equations wherever you need to make a point.

Basic LaTeX Syntax to Get You Started

Here are the building blocks you'll use most often. Each one shows what to type between the tags, and the actual equation it produces.

Exponents (powers): Use the caret symbol ^.

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[latex]x^2[/latex]

Result: \(x^2\)

For exponents with more than one character, wrap them in curly braces {}, or only the first character will end up raised.

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[latex]x^{10}[/latex]

Result: \(x^{10}\)

Subscripts: Use the underscore _.

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[latex]x_1[/latex]

Result: \(x_1\)

Multi-character subscripts need braces too.

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[latex]a_{n+1}[/latex]

Result: \(a_{n+1}\)

Fractions: Use \frac{numerator}{denominator}.

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[latex]\frac{1}{2}[/latex]

Result: \(\frac{1}{2}\)

Square roots: Use \sqrt{...}.

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[latex]\sqrt{2}[/latex]

Result: \(\sqrt{2}\)

For other roots:

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[latex]\sqrt[3]{x}[/latex]

Result: \(\sqrt[3]{x}\)

Greek letters: Type a backslash followed by the letter's name.

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[latex]\alpha + \beta = \gamma[/latex]

Result: \(\alpha + \beta = \gamma\)

Capitalize the first letter for the uppercase version.

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[latex]\Delta[/latex]

Result: \(\Delta\)

Multiplication and division:

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[latex]6 \times 7[/latex]

Result: \(6 \times 7\)

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[latex]10 \div 2[/latex]

Result: \(10 \div 2\)

Common symbols:

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[latex]x \leq 5[/latex]

Result: \(x \leq 5\)

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[latex]x \neq y[/latex]

Result: \(x \neq y\)

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[latex]x \approx 3.14[/latex]

Result: \(x \approx 3.14\)

Sums, products, and integrals: These often work best with the latex_para button, since they take up more vertical space than a normal line of text.

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[latex_para]\sum_{i=1}^{n} i[/latex_para]

Result: \[\sum_{i=1}^{n} i\]

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[latex_para]\int_{0}^{1} x^2 \, dx[/latex_para]

Result: \[\int_{0}^{1} x^2 \, dx\]

A Full Worked Example

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[latex_para]x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}[/latex_para]

Result: \[x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}\]

That's the quadratic formula, fully typeset and centered on its own line, exactly as it would appear in a math textbook.

And inline, using the latex button in the middle of a sentence:

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Einstein's famous equation, [latex]E = mc^2[/latex], relates mass and energy.

Result: Einstein's famous equation, \(E = mc^2\), relates mass and energy.

Tips for Getting It Right

• Curly braces {} group things together. If your exponent, subscript, or fraction has more than one character, wrap it in braces, or only the first character will be affected. x^10 renders wrong — you want x^{10}.
• Backslashes start commands. Almost every named symbol or function (\frac, \sqrt, \alpha, \sum) starts with a backslash. If a symbol isn't rendering, check that you haven't forgotten it.
• Spaces mostly don't matter. LaTeX largely ignores extra spaces in your code, so feel free to space things out for readability — it won't change the rendered result.
• Preview before you post. If your forum's editor has a preview option, use it — it's the fastest way to catch a missing brace or backslash before your post goes live.
• Start simple. You don't need to memorize all of this at once. Even just knowing ^ for exponents and \frac{}{} for fractions will cover a large share of everyday posts.

Where to Learn More

If you want to go beyond the basics — matrices, multi-line equations, special functions, and more — searching "LaTeX math symbols list" will turn up plenty of free reference sheets and symbol tables you can bookmark and refer back to whenever you're unsure how to type something.

That's really all there is to it. Click latex for a quick inline expression, click latex_para for a standalone equation, type your code between the tags, and let MathJax handle the typesetting. Happy posting!