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The Following Relations Are Defined on the Set of Real Numbers. Arb If 1 + Ab > 0 Find Whether These Relations Are Reflexive, Symmetric Or Transitive.

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Question

The following relation is defined on the set of real numbers.

aRb if 1 + ab > 0

Find whether relation is reflexive, symmetric or transitive.

Sum
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Solution

Reflexivity:

Let a be an arbitrary element of R. Then,

∈ R

× 0

i.e. a2 0             [Since, square of any number is positive]

So, the given relation is reflexive.

Symmetry :

Let (a, b∈ R

⇒ 1a0

⇒ 1+b0

⇒ (b, a∈ R

So, the given relation is symmetric.

Transitivity :

Let (a, b)R and (b, c)R

1a0 and 1b>0

But 1a≯ 0

⇒ (a, c∉ R

So, the given relation is not transitive.

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Chapter 1: Relations - Exercise 1.1 [Page 11]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 1 Relations
Exercise 1.1 | Q 5.2 | Page 11

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