Sets-Relations-And-Functions Question 142
Question: Let X and Y be two non-empty sets such that $ X\cap A=Y\cap A=\phi $ and $ X\cup A=Y\cup A $ for some non-empty set A. Then
Options:
A) X is a proper subset of Y
B) Y is a proper subset of X
C) X = Y
D) X and Y are disjoint sets
 Correct Answer: C $ \Rightarrow a\in Y,anda\in A(\therefore X\cup A=Y\cup A) $ $ \Rightarrow a\in Y\cap A\Rightarrow Y\cap A $    is non-empty This contradicts that    $ Y\cap A=\emptyset $     so,    $ X=Y $Show Answer
  Answer:
Solution:
 BETA
  BETA 
             
             
           
           
           
          