Download Chapter 2.4/2.6 Notes: Multiplying and Dividing Real Numbers

Chapter 2.4/2.6 Notes: Multiplying
and Dividing Real Numbers
Goal: You will multiply and divide real
numbers.
• Rules for Multiplying Integers:
• Multiplying two numbers with the same sign will
ALWAYS equal a positive number.
i.e. 4(8) = ___
i.e. -9(-5) = ____
• Multiplying two numbers with different signs will
ALWAYS equal a negative number.
i.e. 4(-9) = ____
i.e. -10(50) = ____
• Find the product.
Ex.1: 2(-5)(-4)
1
Ex.2: (4)(3)
2
Ex.3: -14(2)(-4)
• Properties of Multiplication:
• Property of Zero: The product of a number and 0 is
0.
i.e. -3 • 0 = ___
i.e. 5(0) = ____
• The identity property states that the product of a
number a and 1 is a. The number 1 is called the
multiplicative identity.
1
• The reciprocal of a nonzero number a, written as ,
a
is called the multiplicative inverse of a.
1
i.e. 3   ____
3
1
i.e. 8   ___
8
1
i.e. The multiplicative inverse of
is _____.
5
• Rules for Dividing Integers:
• Dividing two numbers with the same sign will
ALWAYS equal a positive number.
i.e. 28 ÷ 7 = ___
i.e. -15 ÷ -3 = ___
• Dividing two numbers with different signs will
ALWAYS equal a negative number.
i.e. -16 ÷ 4 = ___
i.e. 99 ÷ -11 = ___
• Find the quotient.
Ex.4: 68 ÷ -4
Ex.5: -45 ÷ -15
 5 
Ex.6: 20   
 3 
125
Ex.7:
25