Title: EQUATIONS AND
1Chapter 1
- EQUATIONS AND
- INEQUALITIES
21.1
- Real Numbers and Number Operations
3(No Transcript)
4Natural Numbers This group of numbers starts at
1. It includes 1, 2, 3, 4, 5 Zero is not in this
group. It has no negative numbers. There are no
numbers with decimals.
5Whole Numbers This group has all of the Natural
Numbers in it plus the number 0. 0,1,2,3,4,5,
6Integers This group has all the Whole Numbers in
it and their opposites, or, you might say, and
their negatives. -5,-4,-3,-2,-1,0,1,2,3,4,5
7Rational Numbers This is any number that can be
expressed as a ratio of two integers. Note the
ratio in rational. Examples ½, ¾, -¾ ,
-5/1 When written as decimals, rational numbers
terminate or repeat. Examples ¾ 0.75
1/3 0.333
8Irrational Numbers This is any number that can
not be express as an integer divided by an
integer, (not counting, no pun intended,
imaginary or complex numbers). These numbers have
decimals that never terminate and never repeat
with a pattern. Examples ? , v2, v5
9Real Numbers This group is made up of all the
Rational and Irrational Numbers. The ordinary
number line encountered when studying algebra
holds real numbers.
10Number Line
Origin
0
1
-1
11Properties of Real Numbers
- For all of the following properties
-
- Let a, b, and c be real numbers
12Closure Property
- Addition
- a b
- is a real number
- Multiplication
- ab
- is a real number
13Commutative Property
- Addition
- a b b a
- Multiplication
- ab ba
14Associative Property
- Addition
- (a b) c a (b c)
- Multiplication
- (ab)c a(bc)
15Identity
- Addition
- a 0 a, 0 a a
- Multiplication
- a 1 a, 1 a a
16Inverse
- Addition
- Additive Inverse of any number a is (-a)
- a (-a) 0
- Multiplication
- Multiplicative Inverse of any nonzero a is 1/a
- a(1/a) 1
17Distributive Property
- This property uses both
- Addition and Multiplication
- a (b c) ab ac
- (b c)a ba ca
18Classwork Pg 7-10 (1-14,55) Homework Pg 7-10
(16-56 even)
19Section 1.2
- Algebraic Expressions and Models
20Exponentiation raising a number to a power
2 is the base 5 is the exponent and 25 is the
power
21Order of Operations
- Please Excuse My Dear Aunt Sally
- Parenthesis
- Exponents
- Multiplication/Division (from left to right)
- Addition/Subtraction (from left to right)
22Variable a letter that is used to represent one
or more numbers
23Algebraic Expression an expression involving
variables
24Evaluating Algebraic Expressions
- Substitute values of variables, in other words,
plug in the values or replace the variables with
the values. - Simplify following the order of operations rules
25- Substitute -2 for x
- -3(-2)2 - 5(-2) 7
- Simplify
- -3(4) 10 7 -12 10 7 5