The toolbar button allows to add an `m:math`
top-level MathML element to
your document. For now, this button is found in the toolbar only when you
open a DocBook v5+ document, a DITA topic or an XHTML 5 page.

The
newly inserted `m:math` element contains just an empty
`m:mi` (math identifier) element. Using the
**MathML** tool, you'll be able to replace this placeholder by complex
equations without knowing much about the MathML standard.

The **MathML** tool contains a
number of palettes. Each palette contains a number of MathML
templates.

Clicking on a template replaces the implicitly or explicitly selected element by this template. Remember that the element containing the caret is implicitly selected. Therefore, generally, clicking on a template replaces the element containing the caret.

In practice, this means that using the
**MathML** tool imposes you to construct your equation using a top-down
approach. If you want to write , you cannot write that naturally, from
left to right. You'll have to first insert the template,
then replace the left placeholder by a fraction template , then replace
the right placeholder by another fraction template and so on. This
top-down approach may seem tedious and slow, but it is also easy to
remember and straightforward to use.

Fortunately, in some cases, there are ways to workaround this top-down approach:

- It's possible to type simple expressions in
`m:mi`(math identifier) and`m:mn`elements (math number) and then invoke menu item "**Parse Text As MathML**" (keyboard shortcut`Ctrl+Shift-SPACE`) in order to parse the expression as MathML. For example, if you can type "E = m*c^2" and then press`Ctrl+Shift-SPACE`to let XMLmind XML Editor do all the hard work for you. - If you
`Ctrl-click`or`Shift-click`on a template, this will*wrap*(rather than replace) the implicitly or explicitly selected element in the MathML template clicked upon. - More intuitive, you can use the
*text selection*to specify the MathML element which is the common ancestor of the nodes involved in this selection. And when the text selection is used (as opposed to the implicit or explicit element selection), suffice to click on a template (that is, no need to`Ctrl-click`or`Shift-click`) in order to wrap what has been selected in the MathML template clicked upon.

This being said, if you know MathML, you are free to write your
equations directly using the **Edit** and the **Attributes** tools.
Because XMLmind XML Editor natively supports MathML presentation markup,
MathML elements are not treated differently than say, a paragraph or a
list item.

Suppose that you need to insert the following equation in a DocBook 5 document: .

- Replace the initial empty
`m:mi`(math identifier) element by clicking on the simplest equation template. - Type "
`F`" in the left placeholder. - Replace the right placeholder by clicking on the fraction template.
- Type "
`G*m_1*m_2`" in the numerator of the fraction; press`Ctrl+Shift-SPACE`to invoke "**Parse Text As MathML**"; Click in the popup (or press`Down`then`Enter`, like for any popup menu) to accept what's suggested in the popup.Notice that character "

`*`" is translated by "**Parse Text As MathML**" to what's looks like a small`x`. This very common MathML operator is called`InvisibleTimes`. This operator is peculiar because normally it's invisible. However for easier editing, XMLmind XML Editor has made it visible. - Type "
`d^2`" in the denominator of the fraction; press`Ctrl+Shift-SPACE`to invoke "**Parse Text As MathML**"; press`Down`then`Enter`to accept what's suggested in the popup.Most computer keyboards will allow you to directly type "d

^{2}" in the empty denominator of the fraction. This empty denominator is, like all placeholders, an`m:mi`element. Don't do that because "d^{2}" is clearly not an identifier. In MathML, "d^{2}" is represented by:<m:msup> <m:mi>d</m:mi> <m:mn>2</mn:mn> </m:msup>

and this is exactly what will be suggested by "

**Parse Text As MathML**" if you type "`d^2`" in the denominator of the fraction.