Today's Big Math Term: Commutative Properties, and other notes from today

Examples of the Commutative Property for Addition

• 4 + 2 = 2 + 4
• 5 + 3 + 2 = 5 + 2 + 3
• b + a = a + b (Yes, algebraic expressions are also commutative for addition

 Examples of the Commutative Property for Multiplication

• 4 • 2 = 2 • 4
• 5 • 3 • 2 = 5 • 2 • 3
• a • b = b • a(Yes, algebraic expressions are also commutative for multiplication)

 Subtraction (Not Commutative)

Subtraction is probably an example that you know, intuitively, is not commutative .

• 4 − 2 ≠ 2 − 4
• 4 −3 ≠ 3 − 4
• a − b ≠ b − a

 Division (Not Commutative)

Division is probably an example that you know, intuitively, is not commutative .

• 4 ÷ 2 ≠ 2 ÷ 4
• 4 ÷ 3 ≠ 3 ÷ 4
• a ÷ b ≠ b ÷ a

http://www.mathwarehouse.com/dictionary/C-words/commutative-property.php



Other Terms/Ideas from Today:

Multiplication is also known as repeated addition.

There are 4 ways to write a multiplication expression:

3 x 4 = 12

3 • 4 = 12

(3)(4) = 12
<brackets that are right beside each other with no operation between them imply multiplication>

3*4 = 12 <computer notation>

Today we also defined Prime (only two factors) and Composite (3 or more factors) types of numbers