Solution :
The value of sin 120 degrees is \(\sqrt{3}\over 2\).
Proof :
We Know that sin 60 = \(\sqrt{3}\over 2\) and cos 60 = \(1\over 2\)
By using the formula of sin 2A,
sin 120 = 2 sin 60 cos 60 = 2 \(\times\) \(\sqrt{3}\over 2\) \(\times\) \(1\over 2\)
\(\implies\) sin 120 = \(\sqrt{3}\over 2\)
