Maths · Relations, type of relations, equivalence relations

Let be a relation defined on the set of natural numbers, as \in \boldsymbol{N} \

Let \( \rho \) be a relation defined on \( N, \) the set of natural numbers, as \( \boldsymbol{\rho}=\{(\boldsymbol{x}, \boldsymbol{y}) \in \boldsymbol{N} \times \boldsymbol{N}: \mathbf{2} \boldsymbol{x}+\boldsymbol{y}=\mathbf{4 1}\} \) then

  • A. \( \rho \) is an equivalence relation
  • B. \( \rho \) is only reflexive relation
  • C. \( \rho \) is only symmetric relation
  • D. \( \rho \) is not transitive

Step-by-step solution

The relation ρ is defined by 2x+y=41. For reflexivity, we need 3x=41, which has no natural solution, so not reflexive. For symmetry, if (x,y)∈ρ then 2x+y=41 but 2y+x=41 implies x=y, and no such natural x exists, so not symmetric. For transitivity, take (11,19) and (19,3) in ρ, then (11,3) gives 2*11+3=25≠41, so transitivity fails. Therefore ρ is not transitive, and option D is correct.
Practise more in this unitView MCQsSign up for full question bank