# Set Theory and Algebra MCQ - Sets

71:

Number of proper subsets of a set of order three

 A. 3 B. 6 C. 8 D. 9 Answer Report Discuss Option: B Explanation : Click on Discuss to view users comments. Write your comments here:
72:

If A be a finite set of size n, then number of elements in the power set of A x A is

 A. 22^n B. 2n^2 C. (2n)2 D. none of these Answer Report Discuss Option: B Explanation : If A  is a finite set with |A| = n elements, then the number of powersets of  A is  2n  and here  we have  2 sets of  A i.e. A*A  i.e. A2 so  total elements = n2 So  powersets pf A*A = 2n^2. So answer is (B) Click on Discuss to view users comments. Write your comments here:
73:

Which of the following set (s) are empty ?

 A. {x : x = x} B. {x : x ≠ x} C. {x : x = x2} D. {x : x ≠ x2} Answer Report Discuss Option: B Explanation : Click on Discuss to view users comments. Write your comments here:
74:

If A = {x, y}, then proper subsets of A are

 A. {x},{y} B. Ø,{x,y} C. Ø,{x},{y} D. None of these Answer Report Discuss Option: C Explanation : Click on Discuss to view users comments. Write your comments here:
75:

If R is an equivalence relation on a set A, then R-1 is

 A. relexive B. symmetric C. transitive D. all of these Answer Report Discuss Option: D Explanation : Click on Discuss to view users comments. Write your comments here: