Answers to Exercises
CHAPTER 1
2. 5
3. 252
4. (i) No (ii) No (iii) Yes (iv) boundary of a unit circle and the relation C is called Circle Relation.
5. 236, 26(Hint: Number of elements in X × X is 36 and therefore number of possible subsets is 236. There are 6 elements of the form (a, a) and so the number of reflexive relations is 26.)
7. The relation is not anti-symmetric
8. R = {(1, 1), (2, 2), (3, 3), (4, 4)}
9.

10.

11.

12. (i), since ...
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