Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
In $\triangle A B C$, if $\frac{\cos A}{a}=\frac{\cos B}{b}=\frac{\cos c}{c}$ with usual notations, then the triangle is
MathematicsProperties of TrianglesMHT CETMHT CET 2020 (14 Oct Shift 2)
Options:
  • A an isosceles triangle
  • B an equilateral triangle
  • C a right angled scalene triangle
  • D a scalene triangle
Solution:
1728 Upvotes Verified Answer
The correct answer is: an equilateral triangle
From sine rule $a / \sin A=b / \sin B=c / \sin C=2 R$
Given situation
$a / \cos A=b / \cos B=c / \cos B=k$
$2 R \sin A=k \cos A$
$\tan A=\tan B=\tan C$
Hence it is equilateral triangle.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.