One of the general solutions of `sqrt(3) cos theta -3 sin theta =4 sin – InterviewSolution

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1.	One of the general solutions of `sqrt(3) cos theta -3 sin theta =4 sin 2 theta cos 3 theta` isA. `(3n pm 1) pi//12, AA n in Z`B. `(4n pm 1) pi//9, AA n in Z`C. `(3n pm 1) pi//9, AA n in Z`D. `(3n pm 1) pi//3, AA n in Z`
Answer» Correct Answer - C We have `4 sin theta sin 2 theta sin 4 theta =3 sin theta -4 sin^(3) theta` or `sin theta [4 sin 2 theta sin 4 theta -3 +4 sin^(2) theta]=0` or `sin theta [2(cos 2 theta - cos 6 theta)-3+2 (1- cos 2 theta)]=0` or `sin theta (-2 cos 6 theta -1)=0` or `sin theta =0 or cos 6 theta =-1//2` `rArr theta = n pi or 6 theta =2 n pi pm 2 pi//3, AA n in Z` `= n pi or theta =(3n pm 1) pi//9, AA n in Z`

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