2018-10-12 19:37:13 +00:00
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---
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title: Cross Product
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---
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## Cross Product
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In set theory, a cross product of two sets is a binary operation performed on sets, which outputs a result set.
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It is denoted by the symbol X. Sometimes it is also called as Cartesian Product after mathematician Rene Descartes.
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2019-03-14 16:49:22 +00:00
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Each element of A is paired with each element of B.
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2018-10-12 19:37:13 +00:00
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<pre><code>
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A X B = {(a, b) | a ∈ A and b ∈ B}
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</code></pre>
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### Examples
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```
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let us have,
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set A = {a, b}
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& set B = {1, 2}
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then A X B = {(a, 1), (a, 2),
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(b, 1), (b, 2)}
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```
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### Use
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It is used to generate all possible combinations after combining two tables in a database.
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### References
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[Wikipedia Article](https://en.wikipedia.org/wiki/Cartesian_product)
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[Wofram Alpha](https://www.wolframalpha.com/input/?i=Cartesian+product&lk=1&a=ClashPrefs_*MathWorld.CartesianProduct-)
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