On the set R of all real numbers, a relation R is defined by R = {(a, b) : 1 + ab > 0}. Then R is -Maths 9th

1 Answer

Answer :

(a) Reflexive and symmetric only(a, a) ∈ R ⇒ 1 + a . a = 1 + a2 > 0 V real numbers a ⇒ R is reflexive (a, b) ∈ R ⇒ 1 + ab > 0 ⇒ 1 + ba > 0 ⇒ (b, a) ∈ R ⇒ R is symmetricWe observe that \(\big(1,rac{1}{2}\big)\)∈ R and \(\big(rac{1}{2},-1\big)\) ∈ Rbut (1, – 1) ∉ R as 1 + 1 × (–1) = 0 \( ot>\) 0 ⇒ R is not transitive.

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Last Answer : Solution :-