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Let R Be a Relation on N × N Defined By(A, B) R (C, D) ⇔ A + D = B + C For All (A, B), (C, D) ∈ N × Nshow That:(Ii) (A, B) R (C, D) ⇒ (C, D) R (A, B) for All (A, B), (C, D) ∈ N × N - Mathematics

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Question

Let R be a relation on N × N defined by
(ab) R (cd) ⇔ a + d = b + c for all (ab), (cd) ∈ N × N
Show that:

(ii) (ab) R (cd) ⇒ (cd) R (ab) for all (ab), (cd) ∈ N × N

 

 

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Solution

We are given ,
(ab) R (cd) ⇔ a + d = b + c for all (ab), (cd) ∈ N × N

(ii) (ab) R (cd) ⇒ (cd) R (ab) for all (ab), (cd) ∈ N × N

\[(a, b) R (c, d) \Rightarrow a + d = b + c \]
\[ \Rightarrow c + b = d + a \]
\[ \Rightarrow (c, d) R (a, b)\]

 

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Chapter 2: Relations - Exercise 2.3 [Page 21]

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RD Sharma Mathematics [English] Class 11
Chapter 2 Relations
Exercise 2.3 | Q 22.2 | Page 21

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