Let R be a relation on the set of integers given by a = 2^k .b for some integer k. Then R is -Maths 9th

1 Answer

Answer :

(c) equivalence relationGiven, a R b = a = 2k .b for some integer. Reflexive: a R a ⇒ a = 20.a for k = 0 (an integer). True Symmetric: a R b ⇒ a = 2k b ⇒ b = 2–k . a ⇒ b R a as k, –k are both integers. True Transitive: a R b ⇒ a = 2k1 b b R c ⇒ b = 2k2 c ∴ a = 2k1 . 2k2c = 2k1 + k2 c, k1 + k2 is an integer. ∴ a R b, b R c ⇒ a R c True ∴ R is an equivalence relation.

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