27 lines
913 B
Markdown
27 lines
913 B
Markdown
---
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tags:
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- prealgebra
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- number-theory
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---
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# Prime factorisation
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Prime factorisation is the activity of expressing a composite number as the
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unique product of [prime numbers](Primes%20and%20composites.md). There are two
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main approaches to this:
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- - factor\* trees
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- repeated division by two
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> **Factor trees:** we take a number $n$ and break it down into two factors of
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> $n$. We then repeat this process with the resulting factors working
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> recursively until the numbers we are left with are primes.
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 _The
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prime factors of 27 are 2, 3, 3_
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it doesn't matter which products we choose as the interim factors, we should
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always reach the same outcome:
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