Let $R$ be a relation on $\mathbb{R}$, given by $R=\{(a, b): 3 a-3 b+\sqrt{7}$ is an irrational number $\}$. Then $R$ is
Solution
<b>For reflexive :</b>
<br/><br/>$3 a-3 a+\sqrt{7}$ is an irrational number $\forall a \in R R$ is reflexive
<br/><br/><b>For symmetric :</b>
<br/><br/>Let $3 a-3 b+\sqrt{7}$ is an irrational number
<br/><br/>$\Rightarrow 3 b-3 a+\sqrt{7}$ is an irrational number
<br/><br/>For example, Let $3 a-3 b=\sqrt{7}$
<br/><br/>$\sqrt{7}+\sqrt{7}$ is irrational but $-\sqrt{7}+\sqrt{7}$ is not.
<br/><br/>$\therefore R$ is not symmetric
<br/><br/><b>For transitive :</b>
<br/><br/>Let $3 a-3 b+\sqrt{7}$ is irrational and $3 b-3 c+\sqrt{7}$ is irrational.
<br/><br/>$\Rightarrow 3 a-3 c+\sqrt{7}$ is irrational.
<br/><br/>For example, take $a=0, b=-\sqrt{7}, c=\frac{\sqrt{7}}{3}$
<br/><br/>$R$ is not transitive.
About this question
Subject: Mathematics · Chapter: Sets, Relations and Functions · Topic: Sets and Operations
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