# 11.33. Symbolic Response¶

This topic is planned to document features that the current symbolic response supports. In general, it allows the input and validation of math expressions, up to commutativity and some identities.

## 11.33.1. Features¶

This is a partial list of features, to be revised over time.

• sub and superscripts: an expression following the ^ character indicates exponentiation. To use superscripts in variables, the syntax is b_x__d for the variable b with subscript x and super d.

An example of a problem.

<symbolicresponse expect="a_b^c + b_x__d" size="30">
<textline math="1"
preprocessorClassName="SymbolicMathjaxPreprocessor"
preprocessorSrc="/static/js/capa/symbolic_mathjax_preprocessor.js"/>
</symbolicresponse>


It’s a bit of a pain to enter that.

• The script-style math variant. What would be outputted in latex if you entered \mathcal{N}. This is used in some variables.

An example:

<symbolicresponse expect="scriptN_B + x" size="30">
<textline math="1"/>
</symbolicresponse>


There is no fancy preprocessing needed, but if you had superscripts or something, you would need to include that part.