Page 54 - Math Course 2 (Book 1)

Real Number System

Mo. 2

Lesson 2 Let’s Begin

KEY CONCEPTS:
1. Identify and compare numbers in the Classify Real Numbers
real number system.
2. Solve equations by f nding square roots
Examples

MO. 2 - L2a

Identifying Real Numbers

Vocabulary A-Z

Let us learn some vocabulary
Name all of the sets of numbers to which the real
number 0.246 belongs.

Irrational numbers Answer This repeating decimal is a
244
An irrational number is any real number which rational number because it is equivalent to 990
cannot be expressed as a fraction a/b, where a
and b are integers, with b non-zero.
Name all of the sets of numbers to which the real
number 255 belongs.
π = 3.14159...

0.101001000100001...
Answer Since 255 this number is a
2 = 1.414213562... natural number, a whole number, an integer, and
a rational number.
Real numbers

The set of rational numbers and the set of irrational Name all of the sets of numbers to which the real
72
numbers together make up the set of real numbers. number belongs.
–
6
72
Rational Numbers Answer Since = –12, this number
–
6
2 0.2 0.25 – 1 0.6 Irrational is a natural number, a whole number, an integer,
3 3 Numbers
and a rational number.
Integers
–4 –3 –8 π
0.010010010001...
Whole numbers Name all of the sets of numbers to which the real
14
0 number belongs.
4
Natural numbers 2
14
2 5 Answer Since = 3.5 this number is
4
a natural number, a whole number, an integer,
and a rational number.

46