MCQ
$\sin 4\theta $ can be written as
- ✓$4\sin \theta (1 - 2{\sin ^2}\theta )\sqrt {1 - {{\sin }^2}\theta } $
- B$2\sin \theta \cos \theta {\sin ^2}\theta $
- C$4\sin \theta - 6{\sin ^3}\theta $
- DNone of these
✓
Answer
Correct option: A.
$4\sin \theta (1 - 2{\sin ^2}\theta )\sqrt {1 - {{\sin }^2}\theta } $
a
(a) $\sin 4\theta = 2\sin 2\theta \cos 2\theta $
(a) $\sin 4\theta = 2\sin 2\theta \cos 2\theta $
$ = 2.2\sin \theta \cos \theta (1 - 2{\sin ^2}\theta )$
$ = 4\sin \theta (1 - 2{\sin ^2}\theta )\sqrt {1 - {{\sin }^2}\theta } $
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