1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

A belongs to b, b subset c, a not a subset of c

  1. Sep 5, 2012 #1
    1. The problem statement, all variables and given/known data
    a∈b, b⊆c, a not ⊆ c
    (in other words, the last subset symbol should have a line from top to bottom)

    2. Relevant equations


    none
    3. The attempt at a solution

    ive tried a million things, I cant find anything that doesnt break one of the conditions

    the most recent attempt is that
    A, B and C are all empty sets, but that would imply that a can be an element of B. my logic is that a doesnt contain all the elements of c, because there are no elements of c

    every other thing ive tried has c containing all the elements of B, but since B contains all the elements of A, i run into a logical problem.

    I tried for a long time on this one, and I really need help
     
  2. jcsd
  3. Sep 5, 2012 #2
    This might be an exercise in understanding what ∈ and ⊆ mean, but I'm not sure if you copied the problem correctly. Are you sure that's what it reads?
     
  4. Sep 5, 2012 #3

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    Consider b= {1, 2, 3}, c= {1, 2, 3, 4}, a= 1.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook