# Simplify Symbolic Expression

Simplify symbolic expressions in Live Editor

## Open the Task

To add the **Simplify Symbolic Expression** task to a live
script in the MATLAB Editor:

On the

**Live Editor**tab, select**Task**>**Simplify Symbolic Expression**.In a code block in your script, type a relevant keyword, such as

`simplify`

,`symbolic`

,`rewrite`

,`expand`

, or`combine`

. Select`Simplify Symbolic Expression`

from the suggested command completions.

## Parameters

`Method`

— Specify simplification method

`Simplify`

(default) | `Simplify fraction`

| `Rewrite`

| `Expand`

| `Combine`

Specify the simplification method from the drop-down list:

Simplification Method | Description |
---|---|

`Simplify` | Perform algebraic simplification. |

`Simplify fraction` | Simplify symbolic rational expressions. |

`Rewrite` | Rewrite expressions in terms of another function. |

`Expand` | Expand expressions and simplify inputs of functions by using identities. |

`Combine` | Combine terms of identical algebraic structure. |

`Effort`

— Specify computational effort used to simplify

`Minimum`

(default) | `Low`

| `Medium`

| `High`

| `Full`

Specify the computational effort used for the `Simplify`

method
from the drop-down list:

Simplification Effort | Description |
---|---|

Minimum | Minimum effort with fastest computation time (can return most complicated result) |

Low | Low effort with faster computation time |

Medium | Medium effort with normal computation time |

High | High effort with slower computation time |

Full | Full effort with slowest computation time (can return simplest result) |

`Multiply out brackets`

— Multiply out brackets when expanding expressions

`off`

(default) | `on`

Select this check box to not expand special functions for the
`Expand`

method. This option expands the arithmetic part of an
expression, such as powers and roots, without expanding trigonometric, hyperbolic,
logarithmic, and special functions.

`Ignore analytic constraints`

— Ignore analytic constraints when expanding expressions

`off`

(default) | `on`

Select this check box to apply purely algebraic simplifications to the
`Expand`

method, such as ```
log(a) + log(b) =
log(a*b)
```

with the assumption that `a`

and
`b`

are real positive numbers. Setting ```
Ignore analytic
constraints
```

to `on`

can give you simpler solutions, which
could lead to results not generally valid. This option applies mathematical identities
that are convenient for most engineering workflow, but do not always hold for all values
of variables. In some cases, this option can lead to simpler results that are not
equivalent to the initial expression. For details, see Algorithms.

## Algorithms

When you use `Ignore analytic constraints`

, then the simplification
follows some of these rules:

log(

*a*) + log(*b*) = log(*a*·*b*) for all values of*a*and*b*. In particular, the following equality is valid for all values of*a*,*b*, and*c*:(

*a*·*b*)^{c}=*a*^{c}·*b*^{c}.log(

*a*^{b}) =*b*·log(*a*) for all values of*a*and*b*. In particular, the following equality is valid for all values of*a*,*b*, and*c*:(

*a*^{b})^{c}=*a*^{b·c}.If

*f*and*g*are standard mathematical functions and*f*(*g*(*x*)) =*x*for all small positive numbers,*f*(*g*(*x*)) =*x*is assumed to be valid for all complex values of*x*. In particular:log(

*e*^{x}) =*x*asin(sin(

*x*)) =*x*, acos(cos(*x*)) =*x*, atan(tan(*x*)) =*x*asinh(sinh(

*x*)) =*x*, acosh(cosh(*x*)) =*x*, atanh(tanh(*x*)) =*x*W

_{k}(*x*·*e*^{x}) =*x*for all branch indices*k*of the Lambert W function.

## Version History

**Introduced in R2020a**