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Question
Write the relation in the Roster form and hence find its domain and range :
R1 = {(a, a2) / a is prime number less than 15}
Solution
R1 = {(a, a2) / a is prime number less than 15}
∴ a = 2, 3, 5, 7, 11, 13
∴ a2 = 4, 9, 25, 49, 121, 169
∴ R1 = {(2, 4), (3, 9), (5, 25), (7, 49), (11, 121), (13, 169)}
∴ Domain (R1)
= {a/a is a prime number less than 15}
= {2, 3, 5, 7, 11, 13}
Range (R1)
= {a2 /a is a prime number less than 15}
= {4, 9, 25, 49, 121, 169}
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