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In the Set Z of All Integers, Which of the Following Relation R is Not an Equivalence Relation ?

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प्रश्न

In the set Z of all integers, which of the following relation R is not an equivalence relation ?

विकल्प

  • x R y : if x ≤ y

  • x R y : if x = y

  • x R y : if x − y is an even integer

  • x R y : if x ≡ y (mod 3)

MCQ
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उत्तर

x R y : if x ≤ y

Clearly, R is not symmetric because x < y does not imply y < x.

Hence, (a) is not an equivalence relation.

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अध्याय 1: Relations - Exercise 1.4 [पृष्ठ ३३]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 1 Relations
Exercise 1.4 | Q 26 | पृष्ठ ३३

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