# Homework Help: Trig identity exist?

1. Jul 4, 2012

### kqwan

I look for trig identitiy to simplify this expression:

$$\frac{\sin(nx/2)}{\sin(x/2)}$$

is there one specficic to use, or is there other ones that will help to simplifiy? I have been trying but can't make it simplier!

Thanks!!!!

2. Jul 4, 2012

### tiny-tim

welcome to pf!

hi kqwan! welcome to pf!
i don't think so (unless n = 2)

i think the best you can do is to write sin(nx/2)/sin(x/2) = sin(x/2 + (n-1)x/2)/sin(x/2) …

but that doesn't help much