हिंदी

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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प्रश्न

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.

योग
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उत्तर

Reflexivity:-

Let a be an arbitrary element of R3.

Then, a ∈ R3

⇒ a2 − 4a × 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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अध्याय 1: Relations - Exercise 1.1 [पृष्ठ १०]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 1 Relations
Exercise 1.1 | Q 3.3 | पृष्ठ १०

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