Set theory Flashcards
1
Q
What are natural numbers?
A
N = Positive integers (1, 2, 3, 4, 5…)
2
Q
What are integers?
A
Z = Any number that can be represented without a fraction or decimals (…-3, -2, -1, 0, 1, 2, 3, 4…)
3
Q
What are rational numbers?
A
Q = Any number that can be represented by the ratio of two integers where the denominator is not zero. (-3/2, 10/2, 4/9, 0.33, 3/-2, 0.5, 13/5…)
4
Q
What are irrational numbers?
A
P = Number that cannot be represented by a fraction, decimal expression is non-terminating and non-recurring at any point. (π, √2, e)
5
Q
What are real numbers?
A
R = All rational and irrational numbers
6
Q
What are complex numbers?
A
C = All numbers that can be represented as:
a + bi where a and b are real numbers and I = √ -1
