MCQ
If $2\sin2\theta=\sqrt3$ then $\theta=?$
- ✓$30^\circ$
- B$45^\circ$
- C$60^\circ$
- D$90^\circ$
✓
Answer
Correct option: A.
$30^\circ$
$2\cos2\theta=\sqrt3$
$\Rightarrow\sin2\theta=\frac{\sqrt3}{2}$
$\Rightarrow\sin2\theta=\sin60^\circ$
$\Rightarrow2\theta=60^\circ$
$\Rightarrow\theta=30^\circ$
$\Rightarrow\sin2\theta=\frac{\sqrt3}{2}$
$\Rightarrow\sin2\theta=\sin60^\circ$
$\Rightarrow2\theta=60^\circ$
$\Rightarrow\theta=30^\circ$
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