How do you solve for the exact solutions in the interval [0,2pi] of #sin(3x)cosx - sinx cos(3x) = 0#?
1 Answer
Mar 9, 2016
Explanation:
Apply the trig identity: sin (a - b) = sin a.cos b - sin b.cos a.
sin (3x - x) = sin 3x.cos x - sin x.cos 3x.
sin (3x - x) = sin 2x = 0
sin 2x = 0 --> 2x = 0 --> x = 0; and
sin 2x = 0 -->
sin 2x = 0 -->
