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If R and S Are Transitive Relations on a Set A, Then Prove that R ∪ S May Not Be a Transitive Relation on A.

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प्रश्न

If R and S are transitive relations on a set A, then prove that R ∪ S may not be a transitive relation on A.

योग
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उत्तर

Let  A = {a, b, c} and R and S be two relations on A, given by

R = {(a, a), (a, b), (b, a), (b, b)} and
S = {(b, b), (b, c), (c, b), (c, c)}

Here, the relations R and S are transitive on A.

(a, b∈ ∪ S and (b, c∈ ∪ S

But (a, c∉ ∪ S 

Hence, R ∪ S is not a transitive relation on A.

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अध्याय 1: Relations - Exercise 1.2 [पृष्ठ २७]

APPEARS IN

आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 1 Relations
Exercise 1.2 | Q 16 | पृष्ठ २७

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