# Formula Manipulation and Simplification

Transform your expression into the particular form you require
(expanded, factored, or expressed in particular terms) by choosing
the appropriate function. See Choose Function to Rearrange Expression. If you just
need a simpler expression, use `simplify`

.
You also can substitute for any part of an expression with another
value by using `subs`

.

## Live Editor Tasks

Simplify Symbolic Expression | Simplify symbolic expressions in Live Editor (Since R2020a) |

## Functions

## Topics

**Choose Function to Rearrange Expression**

Several functions are available to manipulate expressions. Understand which function to use.

**Simplify Symbolic Expressions**

Simplifying symbolic expressions, including assumptions and additional options.

**Substitute Variables in Symbolic Expressions**

Substitute variables with other variables, numbers, vectors, or matrices.

**Evaluate Symbolic Expressions Using subs**Evaluate expressions and functions after their variables are assigned values.

**Developing an Algorithm for Undistorting an Image**This example develops a mathematical model using the Symbolic Math Toolbox™ to undistort an image and features a local function in the live script.

**Abbreviate Common Terms in Long Expressions**Simplify the display of long expressions by abbreviating common terms.