If cos A = cos B,,cos Cand A + B + C = pi , t | vedclass

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Question

(d) We have $\cos A = \cos B\cos C$ By triangle property,

$A + B + C = \pi \Rightarrow B + C = \pi - A$ 

$	herefore \cos (B + C) = \cos (\

Vedclass · Accepted Answer

$\frac{1}{2}$

Vedclass · Answer

(d) We have $\cos A = \cos B\cos C$ By triangle property,

$A + B + C = \pi \Rightarrow B + C = \pi - A$ 

$	herefore \cos (B + C) = \cos (\pi - A) \Rightarrow \cos (B + C) = - \cos A$

$ \Rightarrow \cos B\cos C - \sin B\sin C = - \cos B\cos C$

$( \because {m{Given}}\cos A = \cos B\cos C)$ 

$ \Rightarrow 2\cos B\cos C = \sin B\sin C$ 

$ \Rightarrow \frac{{\cos B\cos C}}{{\sin B\sin C}} = \frac{1}{2}$

$\Rightarrow \cot B\cot C = \frac{1}{2}$.

If $\cos A = \cos B\,\,\cos C$and $A + B + C = \pi ,$ then the value of $\cot \,B\,\cot \,C$ is

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