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| The property of a pair of binary algebraic operations (cf. [[Algebraic operation|Algebraic operation]]), expressed by one of the following identities: | | The property of a pair of binary algebraic operations (cf. [[Algebraic operation|Algebraic operation]]), expressed by one of the following identities: |
| + | $$ |
| + | (D1)\ \ \ \ \forall x,y,z\ \ x \otimes (y \oplus z) = (x \otimes y) \oplus (x \otimes z) |
| + | $$ |
| + | $$ |
| + | (D2)\ \ \ \ \forall x,y,z\ \ (x \oplus y) \otimes z = (x \otimes z) \oplus (y \otimes z) |
| + | $$ |
| + | where $\oplus, \otimes$ are the symbols of the binary operations, and $x,y,z$ are object variables. If in a set $A$ two specific binary operations $+, \circ$ are defined, i.e. two mappings |
| + | $$ |
| + | + : A \times A \rightarrow A \ ,\ \ \ \circ : A \times A \rightarrow A |
| + | $$ |
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− | <table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335901.png" /></td> </tr></table>
| + | are given, and the symbols $\oplus, \otimes$ are interpreted as the symbols of the respective operations $+, \circ$ in $A$, one can speak of the truth or falsehood of each one of the formulas D1 and D2 in $A$. If both these formulas are true in $A$, the operation $\circ$ is called distributive with respect to the operation $+$ in $A$. |
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− | <table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335902.png" /></td> </tr></table>
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− | | |
− | where <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335903.png" /> are the symbols of the binary operations, and <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335904.png" /> are object variables. If in a set <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335905.png" /> two specific binary operations <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335906.png" />, <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335907.png" /> are defined, i.e. two mappings
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− | | |
− | <table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335908.png" /></td> </tr></table>
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− | | |
− | are given, and the symbols <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d0335909.png" /> are interpreted as the symbols of the respective operations <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359010.png" /> in <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359011.png" />, one can speak of the truth or falsehood of each one of the formulas D1 and D2 in <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359012.png" />. If both these formulas are true in <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359013.png" />, the operation <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359014.png" /> is called distributive with respect to the operation <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359015.png" /> in <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359016.png" />. | |
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| ====Comments==== | | ====Comments==== |
− | I.e., in <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359017.png" /> the operation <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359018.png" /> is distributive with respect to <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359019.png" /> if for all <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359020.png" /> one has <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359021.png" /> and <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/d/d033/d033590/d03359022.png" />. | + | I.e., in $A$ the operation $\circ$ is distributive with respect to $+$ if for all $a,b,c \in A$ one has $a \circ (b+c) = (a \circ b) + (a \circ c)$ and $(a + b) \circ c = (a \circ c) + (b \circ c)$. |
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| For example, multiplication is distributive with respect to addition in the set of real numbers and in the set of integers. | | For example, multiplication is distributive with respect to addition in the set of real numbers and in the set of integers. |
| + | |
| + | {{TEX|done}} |
Revision as of 19:41, 8 November 2014
distributivity law, distributive property, of one operation with respect to another
The property of a pair of binary algebraic operations (cf. Algebraic operation), expressed by one of the following identities:
$$
(D1)\ \ \ \ \forall x,y,z\ \ x \otimes (y \oplus z) = (x \otimes y) \oplus (x \otimes z)
$$
$$
(D2)\ \ \ \ \forall x,y,z\ \ (x \oplus y) \otimes z = (x \otimes z) \oplus (y \otimes z)
$$
where $\oplus, \otimes$ are the symbols of the binary operations, and $x,y,z$ are object variables. If in a set $A$ two specific binary operations $+, \circ$ are defined, i.e. two mappings
$$
+ : A \times A \rightarrow A \ ,\ \ \ \circ : A \times A \rightarrow A
$$
are given, and the symbols $\oplus, \otimes$ are interpreted as the symbols of the respective operations $+, \circ$ in $A$, one can speak of the truth or falsehood of each one of the formulas D1 and D2 in $A$. If both these formulas are true in $A$, the operation $\circ$ is called distributive with respect to the operation $+$ in $A$.
I.e., in $A$ the operation $\circ$ is distributive with respect to $+$ if for all $a,b,c \in A$ one has $a \circ (b+c) = (a \circ b) + (a \circ c)$ and $(a + b) \circ c = (a \circ c) + (b \circ c)$.
For example, multiplication is distributive with respect to addition in the set of real numbers and in the set of integers.
How to Cite This Entry:
Distributivity. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Distributivity&oldid=14448
This article was adapted from an original article by D.M. Smirnov (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098.
See original article