Unit 1 Lesson 1

integers

(integers, natural, or whole): -2, -1, 0, 1, 2

natural numbers

closed under addition & multiplication, but not subtraction or division

integers

closed under addition, subtraction, and multiplication but not division

rational numbers and real numbers

closed under addition, subtraction, multiplication, and division

irrational

identify as rational or irrational: sq root of 2

irrational

identify as rational/irrational: pi

integers, whole

integers, natural, or whole: 0, 5, 10, 15

integers, whole

integers, natural, or whole: 0, 8, 9, 10

integers, natural, whole

integers, natural, or whole: 4, 5, 6, 7

irrational numbers

never closed

whole numbers

numbers 0, 1, 2, 3, 4...

natural numbers

numbers 1, 2, 3, 4...; designated with N

Rational numbers

numbers of the form {a/b | a, b, E, Z, b =/= 0}; designated with Q

integers

numbers {0, 1, -1, 2, -2...}; designated with Z

rational

rational/irrational: 0.333....

rational

rational/irrational: 5

irrational numbers

real numbers which cannot be written as the ratio of 2 integers; designated with Q with a line over it

closure

the property of an operation & a set that the performance of the operation on members of the set always yields a member of that set

Real numbers

the rational numbers together with the irrational numbers; designated with R