मराठी

The Following Relations is Defined on the Set of Real Numbers. Arb If |A| ≤ B Find Whether Relations Are Reflexive, Symmetric Or Transitive.

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प्रश्न

The following relation is defined on the set of real numbers.  aRb if |a| ≤ b

Find whether relation is reflexive, symmetric or transitive.

बेरीज
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उत्तर

Reflexivity :

Let a be an arbitrary element of R. Then,

 ∈                  [Since, |a|=a]

⇒ |a|≮ a

So, R is not reflexive.

Symmetry :

Let (a, b∈ R

⇒ |a≤ b 

 |b≰ a for all a, ∈ R

⇒ (b, a∉ R 

So, R is not symmetric.

Transitivity :

Let (a, b∈ R and (b, c∈ R

⇒ |a≤ b and |b≤ c

Multiplying the corresponding sides, we get

|a|  |b≤ bc

⇒ |a≤ c

⇒ (a, c∈ R

Thus, R is transitive. 

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पाठ 1: Relations - Exercise 1.1 [पृष्ठ ११]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 1 Relations
Exercise 1.1 | Q 5.3 | पृष्ठ ११

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