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Question

Let R and S be any two equivalence relations on a non-empty set A. Which one of the following statements is TRUE?

a.

R ∪ S, R ∩ S are both equivalence relations

b.

R ∪ S is an equivalence relation

c.

R ∩ S is an equivalence relation

d.

Neither R ∪ S nor R ∩ S is an equivalence relation

Answer: (c).R ∩ S is an equivalence relation

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Q. Let R and S be any two equivalence relations on a non-empty set A. Which one of the following statements is TRUE?

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