Asking for a value of trigonometri

1. Dec 26, 2004

Sanosuke Sagara

I want to ask for what is the value for sin (180-theta/2) ?Thanks for anybody that spend time looking on my problem.

2. Dec 26, 2004

Nylex

Use the fact that sin (A - B) = sin Acos B - cos Asin B.

3. Dec 26, 2004

HallsofIvy

Well, first use the fact that sin(A+B)= sin(A)cos(B)+ cos(A)sin(B)!

And, of course, sin(180)= 0 while cos(180)= -1 (I assume this is in degrees- you didn't actually say so).

If you want this as a function of theta only (again, you didn't say what you really wanted), you will also need to know that sin(theta/2)= +/- &radic;((1/2)(1- cos(theta)).

4. Dec 26, 2004

Nylex

Yeah, sorry that's what I meant . I thought it was obvious to then plug in the values of sin 180 and cos 180.