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Let * be the binary operation defined on Q. Find which of the following binary operations are commutative a * b = (a – b)2 ∀ a, b ∈ Q - Mathematics

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Question

Let * be the binary operation defined on Q. Find which of the following binary operations are commutative

a * b = (a – b)2 ∀ a, b ∈ Q

Sum

Solution

Given that * is a binary operation defined on Q.

a * b = (a – b)2, ∀ a, b ∈Q

b * a = (b –a)2

Since, (a – b)2 = (b – a)2

Thus, * is commutative.

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Chapter 1: Relations And Functions - Exercise [Page 13]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 26. (iv) | Page 13

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