Q18 of 109 Page 1

Let R = {(a, a3) : a is a prime number less than 5} be a relation. Find the range of R.

Given a relation R = {(a, a3) : a is a prime number less than 5}


Now according to the question ‘a’ is a prime number < 5:


⇒ a = {2,3}


⇒ R={(2,8),(3,27)}


⇒ Range of R={8,27)


More from this chapter

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16

Let A = {2, 3, 4, 5} and B = {1, 3, 4}. If R is the relation from A to B given by a R b iff “a is a divisor of b.” Write R as a set of ordered pairs.

 17

State the reason for the relation R on the set {1, 2, 3} given by R = {(1, 2), (2, 1)} not to be transitive.

 19

Show that R is an equivalence relation on the set Z of integers given by R = {(a, b) : 2 divides a – b}. Write the equivalence class [0].

 20

For the set A = {1, 2, 3}, define a relation R on the set A as follows:

R = {(1, 1), (2, 2), (3, 3), (1, 3)}


Write the ordered pairs to be added to R to make the smallest equivalence relation.