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Choose the correct option.
Let L be a set of all straight lines in a plane. The relation R on L defined as 'perpendicular to'…
Let $L$ be a set of all straight lines in a plane. The relation $R$ on $L$ defined as 'perpendicular to' is:
- (a)Symmetric and Transitive
- (b)Transitive
- (c)Symmetric
- (d)Equivalence
Answer
Answer
Correct option: (c)
Answer: (c) Symmetric
If $l_1 \perp l_2$ then $l_2 \perp l_1$, so R is symmetric. A line is not perpendicular to itself (not reflexive), and $l_1 \perp l_2$, $l_2 \perp l_3$ give $l_1 \parallel l_3$, so R is not transitive.