

InterviewSolution
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Prove that : (A ∪ B) x C = (A x C) = (A x C)∪ (B x C) |
Answer» To prove : (A ∪ B) × C = (A × C) ∪ (B × C) Proof : Let (x, y) be an arbitrary element of (A ∪ B) × C. ⇒ (x, y) ∈ (A ∪ B) C Since,(x, y) are elements of Cartesian product of (A ∪ B) × C ⇒ x ∈ (A ∪ B) and y ∈ C ⇒ (x ∈ A or x∈B) and y ∈ C ⇒ (x ∈ A and y ∈ C) or (x ∈ Band y ∈ C) ⇒ (x, y) ∈ A × C or (x, y) ∈ B × C ⇒ (x, y) ∈ (A × C) ∪ (B × C) …1 Let (x, y) be an arbitrary element of (A × C) ∪ (B × C). ⇒ (x, y) ∈ (A × C) ∪ (B × C) ⇒ (x, y) ∈ (A × C) or (x, y) ∈ (B × C) ⇒ (x ∈ A and y ∈ C) or (x ∈ Band y ϵ C) ⇒ (x ∈ A or x ∈ B) and y ∈ C ⇒ x ∈ (A ∪ B) and y ∈ C ⇒ (x, y) ∈ (A ∪ B) × C …2 From 1 and 2, we get : (A ∪ B) × C = (A × C) ∪ (B × C) |
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