Question 18 - Examples - Chapter 1 Class 12 Relation and Functions

Last updated at July 31, 2026 by

Example 35 - Show a * b = a + 2b is not commutative - CBSE - Examples

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Question 18 Show that ∗ : R × R → R defined by a ∗ b = a + 2b is not commutative. We have to prove it is not commutative i.e. a * b ≠ b * a a + 2b ≠ b +2a Let a = 3, b = 4 Since a * b ≠ b * a * is not commutative.

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