AP EAMCET · Maths · Properties of Triangles
In \(\triangle A B C\), if \(\theta\) is any angle, then \(b \cos (C+\theta)+c \cos (B-\theta)=\)
- A \(a \cot \theta\)
- B \(a \cos \theta\)
- C \(a \tan \theta\)
- D \(a \sin \theta\)
Answer & Solution
Correct Answer
(B) \(a \cos \theta\)
Step-by-step Solution
Detailed explanation
Given that, \[ \begin{aligned} b \cos (C+\theta)+c \cos (B-\theta) & \\ =b(\cos C & \cos \theta-\sin C \sin \theta) \\ & +c(\cos B \cos \theta+\sin B \sin \theta) \end{aligned} \]…
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