1. Real Numbers
Section 0.1

2. TERMS you should know Set – A group or collection of objects
Subset – A set of objects that are all members of another set
Ellipsis (…) – The pattern continues
Empty set 0 – A set with no elements
Numerator – Top of a fraction
Denominator – Bottom of a fraction
Constant – A known value
Variable – A letter representing some unknown value
Coefficient – A known value multiplied by a variable

3. Types of numbers Symbol Name Description Examples N Natural Counting
1,2,3,4,… W
Whole
Zero & Natural Numbers
0,1,2,… Z
Integers
zero & positive and negative counting numbers
…,-2,-1,0,1,… Q
Rational
Ratios of integers (repeating or terminating decimals)
-15, -¾, 0, 3.666, 5 I
Irrational
Don’t repeat or terminate R
Real
Rational and Irrational

4. Real Numbers Real Numbers Rational Numbers Irrational Numbers
Whole Numbers
Integers
Natural Numbers

5. Rational or Irrational???
Same as 4.5
Terminates
Rational Number
Same as
Repeats
If it can be written as a ratio of integers it is Rational
Same as …
Doesn’t repeat or terminate
Irrational
Remember all rational and irrational numbers are real numbers

6. Rounding or Truncating
Round to two decimal places
4.68
Truncate (cut off at) to two decimal places
4.67

7. Simplify using the order of operations PEMDAS
3 ( 10 – 3 · 2 ) + 30 – 5 2
= 3 ( 10 – 6 ) + 30 – 5 2
= 3 ( 4 ) + 30 – 5 2
= 3 ( 4 ) + 30 – 25
= – 25
= 42 – 25
= 17

8. Simplify using the order of operations PEMDAS
-3(2x + 4y) – (3x + 7y)
-6x – 12y – 3x – 7y
-9x – 19y

9. Add/Subtract the fractions

10. Simplify

11. Simplify

12. Evaluate the algebraic expression a = 2, b = -3, c = -4
2(2) – 5(-3) ²
2(2) – 5(9)
4 – 45
-41

13. Absolute value- distance from zero
|-2| =2
|-2+7|
=|5| =5