The number of elements in the Power set P(S) of the set S = [ [ Φ] , 1, [ 2, 3 ]] is
A.  2 
B.  4 
C.  8 
D.  None of these 
Option: C Explanation : Click on Discuss to view users comments. mahesh said: (4:49pm on Tuesday 23rd April 2013)
n to the power of 2 is the ansn is 3
Sakthivel said: (11:57am on Friday 19th May 2017)
If u want a set. It should have set bracket. Because in some exam they will ask twisted que.
sahil said: (8:12am on Thursday 1st February 2018)
though this is not the prresentation of set .lets consider above setdn we have its solution as:2 raise to power 3 (i.e the number of elements in given set) so its ans is 8

If A and B are sets and A∪ B= A ∩ B, then
A.  A = Φ 
B.  B = Φ 
C.  A = B 
D.  none of these 
Option: C Explanation : Click on Discuss to view users comments. 
Let S be an infinite set and S_{1}, S_{2}, S_{3}, ..., S_{n} be sets such that S_{1} ∪S_{2} ∪S_{3}∪ .......S_{n} = S then
A.  atleast one of the sets S_{i} is a finite set 
B.  not more than one of the set S_{i} can be inite 
C.  atleast one of the sets S_{i} is an ininite set 
D.  none of these 
Option: C Explanation : Click on Discuss to view users comments. Sakthivel said: (12:13pm on Friday 19th May 2017)
Why can't we say that option a. Its also correct.

If X and Y are two sets, then X ∩ (Y ∪ X) C equals
A.  X 
B.  Y 
C.  Ø 
D.  None of these 
Option: C Explanation : Click on Discuss to view users comments. Usha Kiran said: (10:46pm on Monday 27th February 2017)
if X = {1,2,3} and Y = {4,5,6} then XUY = {1,2,3,4,5,6} and X intersection (XUY) ={1,2,3}therefore answer should be A.
Manzoor Ahmed said: (3:07am on Sunday 16th July 2017)
Should be option A, all the elements which are found in both X and Y U X are same as of X
Bijaya Sen Khadka said: (5:47am on Monday 12th February 2018)
(XUY) has C in its end which means complement. So the answer is not A. (XUY)C has nothing common with X so the answer is C.
Irshad said: (7:53pm on Monday 26th February 2018)
This law is called absorption law so option A
