4.5.1 Number systems Flashcards
1
Q
What is a natural number? ℕ
A
Positive Integers
0, 1, 2, 3…
2
Q
What is an irrational number?
A
A number with an infinite number of decimal places that can’t be written as a fraction
√2 , π…
3
Q
What is a rational number? ℚ
A
A number that can be written as a fraction. All integers are rational numbers.
1/3 , 0.97
4
Q
What is an integer? ℤ
A
Any whole positive or negative number.
-2, -1, 0, 1, 2…
5
Q
What is a real / float number? ℝ
A
Natural, rational and irrational numbers. All possible real world quantities, meaning any number that isn’t imaginary.
6
Q
What are ordinal numbers?
A
Numbers that tell the position of objects when placed in order.
First, second, third…
a, b, c, d…
