# What strategies are used to index content that contains mathematical equations or symbols?

Effectively indexing content that contains mathematical equations or symbols in DITA XML can enhance the accessibility and usability of technical documents. Mathematical content often requires specialized handling to ensure clarity and accuracy in representation. Below, we outline key strategies for indexing such content:

## MathML Integration

One powerful method for handling mathematical content in DITA is to integrate MathML (Mathematical Markup Language). MathML is an XML-based language specifically designed for representing mathematical notation and content. By embedding MathML within your DITA documents, you can accurately display mathematical equations and symbols. Ensure that your DITA processing system supports MathML rendering for optimal results.

## Symbol Definitions

Another strategy is to create a centralized symbol definitions repository. Define mathematical symbols and equations in dedicated DITA topics or elements. These definitions can include notations, explanations, and contextual usage examples. Using DITA’s linking mechanisms, you can easily reference and index these symbols wherever they appear in your documentation. This approach helps users quickly understand and navigate mathematical content.

## Mathematical Content Example:

Here’s an example of how to integrate mathematical content with MathML in DITA:

```
<equation id="quadratic_formula">
<title>Quadratic Formula</title>
<mathml>
<math >
<apply>
<eq/>
<apply>
<times/>
<cn>−b</cn>
<apply>
<plus/>
<apply>
<power/>
<ci>b</ci>
<cn>2</cn>
</apply>
<apply>
<times/>
<cn>4</cn>
<ci>a</ci>
<ci>c</ci>
</apply>
</apply>
</apply>
<apply>
<times/>
<cn>2</cn>
<ci>a</ci>
</apply>
</apply>
</math>
</mathml>
<description>The quadratic formula is used to solve quadratic equations.</description>
</equation>
```

In this example, the <equation> element integrates the quadratic formula using MathML, accompanied by a description. This allows precise representation and indexing of mathematical content within your DITA documentation.