AP EAMCET · Maths · Properties of Triangles
In \(\triangle A B C\), if \(a, b\) and \(c\) are in arithmetic progression, then \(\cos A+2 \cos B+\cos C=\)
- A 1
- B 2
- C \(\frac{3}{2}\)
- D \(\sqrt{3}+1\)
Answer & Solution
Correct Answer
(B) 2
Step-by-step Solution
Detailed explanation
It is given, that in \(\triangle A B C, a, b, c\) are in \(\mathrm{AP}\) So, \(2 b=a+c\)...(i) Now, \(\cos A+2 \cos B+2 \cos C\)…
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