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) Ex.2:  2 1   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 , is called the multiplicative inverse of a.

a

i.e. ____ i.e. ___ 3 8 8  i.e. The multiplicative inverse of is _____. 5 1

• •

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 Ex.6: Ex.7: 3  125  25