Write ‘yes’ if each of the following relations is an equivalence relation. -Maths 9th

1 Answer

Answer :

(i) ‘is parallel to’ is reflexive, because any line is parallel to itself. Symmetric, because if line l is parallel to line m, then line m is parallel to line l. Transitive, because if l || m and m || n then l || n. Therefore,’is parallel to’ is an equivalence relation. (ii) No, because this relation is only symmetric. (iii) No, because this relation is only transitive. It is neither reflexive nor symmetric. (iv) No, because this relation is only reflexive and transitive. It is not symmetric. If x is a factor of y, and x ≠ y, y cannot be a factor of x. (v) No, because the relation is reflexive and transitive but not symmetric.

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