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Test whether the following relation R3 is (i) reflexive (ii) symmetric and (iii) transitive: R3 on R is defined by (a, b) ∈ R3 ⇔ a2 – 4ab + 3b2 = 0.

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Question

Test whether the following relation R3 is (i) reflexive (ii) symmetric and (iii) transitive:

R3 on R is defined by (a, b) ∈ R3 `⇔` a2 – 4ab + 3b2 = 0.

Sum
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Solution

Reflexivity:-

Let a be an arbitrary element of R3.

Then, ∈ R3

⇒ a− 4× a 3a2 0 

So, R3 is reflexive.

Symmetry:-

Let (a, b∈ R3

⇒ a2 4ab + 3b2 = 0

But b2 4ba + 3a2 0 for all a, b ∈ R

So, R3 is not symmetric.

Transitivity:-

Let (1, 2∈ R3 and (2, 3∈ R3

⇒ 1 8 + 6 = 0 and 4 24 + 27 = 0

7 + 6 = 0 and 20 + 27 = 0

1 ≠ 0 and 7 ≠ 0

So, R3 is not transitive.

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Chapter 1: Relations - Exercise 1.1 [Page 10]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.1 | Q 3.3 | Page 10

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