How can I isolate beta in this trigonometric equation?

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Homework Statement



i want to find the beta of this equation. i mean beta in one side and all other things next side. it is ok even if you provide the final answer without calculations.

Homework Equations



-2R*sin(\beta/2)*cos(K-\beta/2)/sin(K+\beta)=d


The Attempt at a Solution

 
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What have you tried so far?

I suggest that you first expand cos(k-β/2) and sin(k+β) and then use the half-angle trig identities to get rid of β/2 in favor of β.
 
kuruman said:
What have you tried so far?

I suggest that you first expand cos(k-β/2) and sin(k+β) and then use the half-angle trig identities to get rid of β/2 in favor of β.

thanks. i did try to expand it but I am zero in maths. please help
 
I have provided help by telling you what to do, but I am not going to do it for you. You can find the identities you need to do what I suggested in

http://www.sosmath.com/trig/Trig5/trig5/trig5.html

Look under "Sum-difference formulas" and "Double angle formulas." Begin by multiplying both sides of the equation by sin(K+β). If you get stuck, ask for help but show your work.
 
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