If sin theta + sin 2theta + sin 3theta = sin | vedclass

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Question

(a) $\sin 	heta + \sin \,3	heta + \sin \,2	heta = \sin \,\alpha $

==> $2\sin 2	heta \cos 	heta + \sin 2	heta = \sin \alpha $ 

==&g

Vedclass · Accepted Answer

$\alpha /2$

Vedclass · Answer

(a) $\sin 	heta + \sin \,3	heta + \sin \,2	heta = \sin \,\alpha $

==> $2\sin 2	heta \cos 	heta + \sin 2	heta = \sin \alpha $ 

==> $\sin 2	heta (2\cos 	heta + 1) = \sin \alpha $&hellip;..$(i)$

Now $\cos 	heta + \cos 3	heta + \cos 2	heta = \cos \alpha $

$2\cos 2\,	heta \cos \,	heta + \cos 2	heta = \cos \alpha $

$\cos 2	heta \,(2\cos 	heta + 1) = \cos \alpha $&hellip;..$(ii) $

From $(i)$ અને $(ii), $

$	an 2	heta = 	an \alpha $

==> $2	heta = \alpha $ 

==> $	heta = \alpha /2$.

If $\sin \theta + \sin 2\theta + \sin 3\theta = \sin \alpha $and $\cos \theta + \cos 2\theta + \cos 3\theta = \cos \alpha $, then $\theta$ is equal to

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