# ExpandNumerator

ExpandNumerator[expr]

expands out products and powers that appear in the numerator of expr.

# Details and Options

• ExpandNumerator works on terms that have positive integer exponents.
• ExpandNumerator applies only to the top level in expr.
• ExpandNumerator automatically threads over lists, as well as equations, inequalities, and logic functions.

# Examples

open allclose all

## Basic Examples(2)

Expand the numerator of a fraction:

Expand a numerator involving multiple variables:

## Scope(7)

Expand the numerator of a rational function:

ExpandNumerator threads over Boolean combinations of equations and inequalities:

ExpandNumerator does not separate the fraction; Expand does:

Expand numerator of a fraction involving arbitrary functions:

Expand the numerator using expansion formulas for trigonometric functions:

Expand the numerator over the integers modulo :

## Options(2)

### Modulus(1)

Expand the numerator over the integers modulo 3:

### Trig(1)

Expand the numerator using expansion formulas for trigonometric functions:

## Applications(1)

ExpandNumerator can be used to verify that two expressions are equal:

## Properties & Relations(5)

ExpandNumerator leaves the denominator unexpanded:

ExpandDenominator expands the denominator, leaving the numerator unexpanded:

Expand expands the numerator and expands the fraction into a sum of fractions:

ExpandAll expands the numerator, the denominator, and the fraction:

Use Factor, Numerator, and Denominator to factor the numerator back:

Wolfram Research (1988), ExpandNumerator, Wolfram Language function, https://reference.wolfram.com/language/ref/ExpandNumerator.html (updated 2007).

#### Text

Wolfram Research (1988), ExpandNumerator, Wolfram Language function, https://reference.wolfram.com/language/ref/ExpandNumerator.html (updated 2007).

#### CMS

Wolfram Language. 1988. "ExpandNumerator." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2007. https://reference.wolfram.com/language/ref/ExpandNumerator.html.

#### APA

Wolfram Language. (1988). ExpandNumerator. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ExpandNumerator.html

#### BibTeX

@misc{reference.wolfram_2024_expandnumerator, author="Wolfram Research", title="{ExpandNumerator}", year="2007", howpublished="\url{https://reference.wolfram.com/language/ref/ExpandNumerator.html}", note=[Accessed: 20-May-2024 ]}

#### BibLaTeX

@online{reference.wolfram_2024_expandnumerator, organization={Wolfram Research}, title={ExpandNumerator}, year={2007}, url={https://reference.wolfram.com/language/ref/ExpandNumerator.html}, note=[Accessed: 20-May-2024 ]}