trig. problem: sin(5x/2)-sin(3x/2)-sin(x/2)=0

[jnersn]

Hi.

Need help with a trigonometry problem. I have sin(5x/2)-sin(3x/2)-sin(x/2)=0 . And don't know how to continue to solve the problem.. Any ideas on what's the next step?

 

[Deleted member 4993]

Hi.

Need help with a trigonometry problem. I have sin(5x/2)-sin(3x/2)-sin(x/2)=0 . And don't know how to continue to solve the problem.. Any ideas on what's the next step?

Hints:

substitute

\(\displaystyle \frac{x}{2} \, = \, \theta\)

and

sin(5a) = sin(4a +a)

sin (3a) = sin (4a - a)

and

\(\displaystyle \sin (A \pm B) \, = \, \sin (A)\cdot \cos (B) \pm \sin (B)\cdot \cos (A)\)

If you are still stuck, write bac showing your work and exactly where you are stuck, so that we know where to begin to help you.