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प्रश्न
Mark the correct alternative in the following question:
Let L denote the set of all straight lines in a plane. Let a relation R be defined by lRm if l is perpendicular to m for all l, m ∈ L. Then, R is ______________ .
विकल्प
reflexive
symmetric
transitive
none of these
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उत्तर
Hence, R is symmetric.
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