Recent content by john-ice2023

  1. john-ice2023

    Are the following statements true? (1) a∈{{a},{a,b}} and (2) b∈{{a},{a,b}} true?

    This is not homework. I saw it on the Internet. I just want to learn something new.
  2. john-ice2023

    Are the following statements true? (1) a∈{{a},{a,b}} and (2) b∈{{a},{a,b}} true?

    TL;DR Summary: Look deep into nature, and then you will understand everything better. Albert Einstein. I am new to set theory. I got confused about above questions. For Q(1), I have two solutions, (a) because a is not the element of set {{a},{a,b}}, so a∈{{a},{a,b}} is False. (b) because...