Prime Factorization

Topics for Today:

Today we discussed prime numbers and prime factorization.  A prime number is a number that has exactly two factors:  one and itself.  We used our divisibility rules from yesterday to help us break numbers down into their prime factors in preparation for simplifying fractions as well as finding common denominators.  Prime factorization is a technique that can be used for many mathematical purposes.  We also completed the Sieve of Eratosthenes to help us identify all the prime numbers between 1 and 100.  

Vocabulary:

prime factorization, prime number, composite number, Least Common Multiple, LCM,

Greatest Common Factor, GCF, multiple

Sections Covered in Textbook:

3-4: Prime Factorization 

Resources & Tutorials:

1) What is a Prime Number?

2) What are Prime and Composite Numbers?

3) How Do you Find Prime Factorization Using a Factor Tree?

4) Sieve of Eratosthenes

Divisibility Rules

Topics for Today:

Today we discussed the rules for divisibility.  A number is divisible by another if it can be divided by it with no remainder.  Knowing divisibility rules helps with simplifying fractions and prime factorization. 

Vocabulary:

divisible

Sections Covered in Textbook:

3-3: Divisibility Tests (pages 141-144)

Resources & Tutorials:

1)  What does divisibility mean?

2)  How do you check if a number is divisible by 2, 3, 5, 6, and 10?

Extras:

It's Amazing Worksheet (Number Theory)