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Defines a Relation On N : X + Y = 10, X, Y∈ N Determine Which of the Above Relations Are Reflexive, Symmetric and Transitive [Ncert Exemplar]

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प्रश्न

Defines a relation on :

x + y = 10, xy∈ N

Determine the above relation is reflexive, symmetric and transitive.

योग
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उत्तर

We have,

R = {(xy) : x + y = 10, xy ∈ N}

R{(1,9),(2,8),(3,7),(4,6),(5,5),(6,4),(7,3),(8,2),(9,1)}

As, (1,1∉ R

So, R is not a reflexive relation

Let (x,y∈ R

⇒ x+10

⇒ y+10

⇒ (y,xR

So, R is a symmeteric relation

As, (1,9∈ R and (9,1∈ R but (1,1∉ R

So, R is not a transitive relation

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अध्याय 1: Relations - Exercise 1.1 [पृष्ठ ११]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 1 Relations
Exercise 1.1 | Q 18.2 | पृष्ठ ११

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