Difference between revisions of "Commutative property"
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In mathematics, the '''commutative property''' states that a [[binary operation]] <math>*</math> on a set '''A''' is said to be commutative if for all <math>x,y</math> in '''A''' we have <math>x*y=y*x</math>. An example of a commutative operation is [[addition]] in the set of [[real numbers]]. When a [[Group (mathematics)|group]]'s operation is commutative, it is said to be [[abelian]]. If <math>x*y=-(y*x)</math>, then the operation is said to be '''anticommutative'''. | In mathematics, the '''commutative property''' states that a [[binary operation]] <math>*</math> on a set '''A''' is said to be commutative if for all <math>x,y</math> in '''A''' we have <math>x*y=y*x</math>. An example of a commutative operation is [[addition]] in the set of [[real numbers]]. When a [[Group (mathematics)|group]]'s operation is commutative, it is said to be [[abelian]]. If <math>x*y=-(y*x)</math>, then the operation is said to be '''anticommutative'''. | ||
| − | In layman's terms, an equation demonstrates commutativity when the constants or variables can be moved around an operation without changing the answer (e.g. 1 + 2 = 2 + 1 or 2 * 3 = 3 * 2). It is as if the numbers are "commuting" from one place to another. Thus, using real numbers, both multiplication and addition are commutative, and subtraction and division are not. For [[vector]]s, the dot product is commutative, while the cross product is anticommutative. | + | In layman's terms, an equation demonstrates commutativity when the constants or variables can be moved around an operation without changing the answer (e.g. 1 + 2 = 2 + 1 or 2 * 3 = 3 * 2). It is as if the numbers are "commuting" from one place to another. Thus, using real numbers, both multiplication and addition are commutative, and subtraction and division are not. For [[vector]]s, the [[dot product]] is commutative, while the [[cross product]] is anticommutative. |
The commutative property <strike>implies</strike> does not imply the [[associative property]]. | The commutative property <strike>implies</strike> does not imply the [[associative property]]. | ||
[[Category:Mathematics]] | [[Category:Mathematics]] | ||
Revision as of 20:58, January 27, 2012
In mathematics, the commutative property states that a binary operation Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle *} on a set A is said to be commutative if for all Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x,y} in A we have Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x*y=y*x} . An example of a commutative operation is addition in the set of real numbers. When a group's operation is commutative, it is said to be abelian. If Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle x*y=-(y*x)} , then the operation is said to be anticommutative.
In layman's terms, an equation demonstrates commutativity when the constants or variables can be moved around an operation without changing the answer (e.g. 1 + 2 = 2 + 1 or 2 * 3 = 3 * 2). It is as if the numbers are "commuting" from one place to another. Thus, using real numbers, both multiplication and addition are commutative, and subtraction and division are not. For vectors, the dot product is commutative, while the cross product is anticommutative.
The commutative property implies does not imply the associative property.