A) \[\frac{\sqrt{5}-1}{4}\]
B) \[\frac{-\sqrt{5}-1}{4}\]
C) 0
D) None of these
Correct Answer: A
Solution :
\[\sin 2\theta =\cos 3\theta \]\[\Rightarrow \] \[3\theta =2n\pi \pm \left( \frac{\pi }{2}-2\theta \right)\] \[\Rightarrow \] \[\theta =\frac{2n\pi }{5}+\frac{\pi }{10}\] or \[\theta =2n\pi -\frac{\pi }{2}\]. Since \[\theta \] is acute Þ \[\theta =\frac{\pi }{10}\] Þ \[\sin \theta =\frac{\sqrt{5}-1}{4}\].You need to login to perform this action.
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