1. Algebra II (Honors) Chapter 1
St. Augustine Preparatory School
2015/2016

2. Real Numbers What are real numbers?
Any number that can be placed on a number line.
Let’s take a look at -4, -2.5, the square root of 2, and pi.

3. Real numbers can be broken into categories
Natural Numbers
Whole Numbers
Integers
Rational Numbers and
Irrational Numbers

4. Real numbers can be broken into categories
Natural Numbers – you use these to count from 1, upwards.
N = {1, 2, 3, 4,….)
Whole Numbers – all of the natural numbers and zero
W = {0, 1, 2, 3, 4….)
Integers – all of the natural numbers, their opposites, and zero.
I = {…-2, -1, 0, 1, 2…}

5. Real numbers can be broken into categories
Rational Numbers:
- All numbers that can be written as a quotient of integers (a/b, b cannot = 0)
- Includes terminating decimals and repeating decimals
- Examples: 1/8, 1/9, 1/3, 12/25

6. Real numbers can be broken into categories
Irrational Numbers:
- Have decimals that neither terminate or repeat
- Examples:
pi = ….
sqrt(2) = ….
- These numbers cannot be written as quotients of integers

8. Classify the following numbers
i) pi
j) 9/4 k)
sqrt(4) l) 179
sqrt (5) m) 3.45x102
4/9

9. Number Lines
Place the following on a number line (without a calculator):
-5/2 , sqrt(2), …, and 4.

10. Number Lines Number lines of inequalities: 2 < x ≤ 4
x > 4 or x < 2

11. Practice Questions
Page 15 #24-34
Page 16 # 57-59