FactorList[poly]
gives a list of the factors of a polynomial, together with their exponents.


FactorList
FactorList[poly]
gives a list of the factors of a polynomial, together with their exponents.
Details and Options

- The first element of the list is always the overall numerical factor. It is {1,1} if there is no overall numerical factor.
- FactorList takes the following options:
-
Extension None generators for the algebraic number field to be used GaussianIntegers False whether to allow Gaussian integer coefficients Modulus 0 modulus to assume for integers Trig False whether to do trigonometric as well as algebraic transformations - FactorList[poly,Modulus->p] requires that p be prime.
- FactorList[poly,Extension->{a1,a2,…}] allows coefficients that are arbitrary rational combinations of the ai.
Examples
open all close allBasic Examples (2)
Scope (11)
Basic Uses (4)
Advanced Uses (7)
The irreducible factors over the Gaussian integers:
The irreducible factors over an algebraic extension:
The irreducible factors over the integers modulo 2:
The irreducible factors over a finite field:
The irreducible factors over an extension of a finite field:
A polynomial irreducible over factors after embedding
in a larger field
:
Options (7)
Applications (2)
FactorList can be useful in determining the behavior of functions:
has roots at
and
, at
it does not cross the
axis, and at
it crosses the
axis:
Show that a polynomial is a perfect square:
Compute the factors and note that the constant factor is positive:
Extract the exponents of nonconstant factors:
Check that every factor has even exponent and thus is a square:
Properties & Relations (3)
FactorList gives a list of irreducible factors:
This multiplies the factors together:
Factor gives a product of factors:
Expand combines all the factors back together:
FactorSquareFreeList gives a list of square-free factors:
FactorInteger gives a list of prime factors of an integer:
Tech Notes
Related Guides
History
Introduced in 1988 (1.0) | Updated in 1996 (3.0) ▪ 2022 (13.2) ▪ 2023 (13.3)
Text
Wolfram Research (1988), FactorList, Wolfram Language function, https://reference.wolfram.com/language/ref/FactorList.html (updated 2023).
CMS
Wolfram Language. 1988. "FactorList." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2023. https://reference.wolfram.com/language/ref/FactorList.html.
APA
Wolfram Language. (1988). FactorList. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/FactorList.html
BibTeX
@misc{reference.wolfram_2025_factorlist, author="Wolfram Research", title="{FactorList}", year="2023", howpublished="\url{https://reference.wolfram.com/language/ref/FactorList.html}", note=[Accessed: 11-August-2025]}
BibLaTeX
@online{reference.wolfram_2025_factorlist, organization={Wolfram Research}, title={FactorList}, year={2023}, url={https://reference.wolfram.com/language/ref/FactorList.html}, note=[Accessed: 11-August-2025]}