मराठी

Test Whether the Following Relations R1 Are (I) Reflexive (Ii) Symmetric and (Iii) Transitive : R1 On Q0 Defined by (A, B) ∈ R1 ⇔ A = 1/B. - Mathematics

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प्रश्न

Test whether the following relation R1 is  (i) reflexive (ii) symmetric and (iii) transitive :

R1 on Q0 defined by (a, b) ∈ R1 ⇔ = 1/b.

बेरीज
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उत्तर

1. Reflexivity:
Let a be an arbitrary element of R1. Then,

a ∈ R1

⇒ a ≠1/a for all a ∈ Q0

So, R1 is not reflexive.

2. Symmetry:
Let (a, b) ∈ R1 Then,

(a, b) ∈ R1

 a =`1/b`

⇒ `b = 1/a`

⇒ `(b, a) ∈ R_1`

So, R1 is symmetric.

3. Transitivity:
Here,

(a, b) ∈ R1 and (b, c) ∈R2

⇒ `a = 1/b and b = 1/c `

⇒ `a = 1/(1/c)=c`

⇒ `a ≠ 1/c`

⇒ (a ,c) ∉ R1

So, R1 is not transitive.

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पाठ 1: Relations - Exercise 1.1 [पृष्ठ १०]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 1 Relations
Exercise 1.1 | Q 3.1 | पृष्ठ १०

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