Find out all kinds of symbols and meanings in the mathematics set of senior one, such as: true inclusion, inclusion waiting ... thank you.

To solve the relationship between sets, we mainly look at the elements of two sets.

For example: (1) A = {1, 2,3}, B = {1, 2}

The elements in B can be found in A, which is a subset of A, so we say that A is contained in B or A is really contained in B..

(2) if A = {1, 2,3}, B = {1, 2,3}

The elements in A are the same as those in B, so we say A = B.

(3)A is contained in B, and A can be less than or equal to B.

A is really contained in B, A is the proper subset of B, and the number of elements in A is less than B..

Use belonging or not between an element and a set (if such a number is found in a set, we say that the element belongs to the set, and vice versa)

For example: A={ 1, 2,3}

Welcome questions!

1 belongs to a, and 4 does not belong to a.