Any set of numbers that contains it. For example: {1,2,3,-0.002} {sqrt(1), pi2, 1/93, -0.002, -73}
It means that the boundaries of the set are not included in the set. For example, consider the set of numbers that are bigger than 1 and smaller than 2. The set is bounded by 1 and 2 but neither of these belong to the set.
Irrational numbers.
It belongs to the rational numbers which is a subset of the real numbers. The reals, in turn, is a subset of complex numbers.
Rational because it can be expressed as a fraction in the form of -50/1
odd numbers, perfect square numbers
The set of numbers which 3 does not belong is the set of even numbers.
10 belongs to the set "natural numbers", but it can also belong to whole numbers, and rational numbers
Any set of numbers that contains it. For example: {1,2,3,-0.002} {sqrt(1), pi2, 1/93, -0.002, -73}
It means that the boundaries of the set are not included in the set. For example, consider the set of numbers that are bigger than 1 and smaller than 2. The set is bounded by 1 and 2 but neither of these belong to the set.
Counting numbers
Irrational numbers.
The set of even numbers
It belongs to the rational numbers which is a subset of the real numbers. The reals, in turn, is a subset of complex numbers.
It belongs to the set of prime numbers
Rational because it can be expressed as a fraction in the form of -50/1
Rational and Real numbers