AP EAMCET · Maths · Properties of Triangles
In any \(\triangle A B C, \frac{\cos A}{a}+\frac{\cos B}{b}+\frac{\cos C}{c}=\)
- A \(a^2+b^2+c^2\)
- B \(\frac{a^2+b^2+c^2}{2 a b c}\)
- C \(\frac{2 a b c}{a^2+b^2+c^2}\)
- D \(a+b+c\)
Answer & Solution
Correct Answer
(B) \(\frac{a^2+b^2+c^2}{2 a b c}\)
Step-by-step Solution
Detailed explanation
Given, in a \(\triangle A B C\), \(\frac{\cos A}{a}+\frac{\cos B}{b}+\frac{\cos C}{c}\) We know that, \(\begin{aligned} & \cos A=\frac{b^2+c^2-a^2}{2 b c}, \\ & \cos B=\frac{a^2+c^2-b^2}{2 a c} \\ & \cos C=\frac{a^2+b^2-c^2}{2 a b}\end{aligned}\) Since,…
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