Edexcel IGCSE Maths复习笔记 1.3.1 Prime Factors

What are prime factors?

• Factors are things that are multiplied together
• Prime numbers are numbers which can only be divided by themselves and 1
• The prime factors of a number are therefore all the prime numbers which multiply to give that number
• You should remember the first few prime numbers:2, 3, 5, 7, 11, 13, 17, 19, …

How to find prime factors

• Use a FACTOR TREE to find prime factors
• Write the prime factors IN ASCENDING ORDER with × between
• Write with POWERS if asked

Language

This is one of those topics where questions can use different phrases that all mean the same thing …

• Express … as the product of prime factors
• Find the prime factor decomposition of …
• Find the prime factorisation of …