Quandaries and Queries


Name :  Muhammad

Status :  Student.

Level :   Secondary.


Let A be a set and let B = {A,{A}}.

(a) Explain the elements of set B (with some example)

(b) Prove that A is not a subset of B.



Hi Muhammad,

B is a set with two elements. They are listed in the description of B. The two elements of B are A and {A}. For example if A={1,2,3} then the two elements of B are {1,2,3} and {{1,2,3}}. I just took the letter A in the third sentence and replaced it by {1,2,3}.

If A is a subset of B then every element of A is also an element of B. 1 is an element of A. Is 1 an element of B?




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