2022-04-23 13:26:53 +01:00
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---
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2022-09-06 13:26:44 +01:00
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tags:
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- prealgebra
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2023-02-10 18:22:04 +00:00
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- number-theory
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2022-04-23 13:26:53 +01:00
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---
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### Prime factorisation
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2024-02-02 15:58:13 +00:00
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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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2024-02-02 15:58:13 +00:00
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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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2024-02-17 11:57:44 +00:00
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2022-09-06 13:26:44 +01:00
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_The prime factors of 27 are 2, 3, 3_
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2024-02-02 15:58:13 +00:00
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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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2024-02-17 11:57:44 +00:00
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2022-04-23 13:26:53 +01:00
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2024-02-17 11:57:44 +00:00
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