If and
find the value of sin 4x.
Given:
To find: Values of sin4x
We know,
sin2 x + cos2 x = 1
⇒ cos2 x = 1 – sin2 x
Since,
⇒cosx will be negative in first quadrant
So,
We know,
sin 2x = 2 sin x cos x
cos 2x = 2 cos2 x – 1
Therefore,
sin 4x = 2 sin 2x cos 2x
⇒ sin 4x = 2 (2 sin x cos x) (2 cos2 x – 1)
Hence, value of