25 lines
		
	
	
	
		
			941 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			25 lines
		
	
	
	
		
			941 B
		
	
	
	
		
			Markdown
		
	
	
	
	
	
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								tags:
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								  - Mathematics
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								  - Prealgebra
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								  - factors primes
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								### Prime factorisation
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								Prime factorisation is the activity of expressing a composite number as the unique product of [prime numbers](Primes%20and%20composites.md). There are two main approaches to this:
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								* * factor* trees
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								* repeated division by two
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								 > 
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								 > **Factor trees:** we take a number $n$ and break it down into two factors of $n$. We then repeat this process with the resulting factors working recursively until the numbers we are left with are primes.
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								*The 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 always reach the same outcome:
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