B What values of m as a function of q satisfy this trigonometric equation?

AI Thread Summary
The discussion centers on solving the trigonometric equation 2sin(qπ/m) - sin(qπ/2) = 0 for values of m as a function of q. The obvious solution is when q equals 2n and m equals 2, where n is an integer. The user derived an expression for m as m = qπ/arcsin(1/2sin(qπ/2)), which yields integer values for q/m when q is of the form 2n. There is a suggestion to incorporate additional terms like +2πk to find other solutions for m. The participants express uncertainty about finding a simpler expression that excludes trigonometric functions.
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I have a trigonometric equation
2\sin \left ( \frac{q\pi }{m} \right )-\sin \left ( \frac{q\pi }{2} \right )=0
and want to know what values m as a function of q could take to satisfy the equation. Both terms zero is the obvious solution: q=2n; m=2; n is an integer. But there are more solutions. I tried to use different kinds of trigonometric identities, with no luck.
The best I could get is
m=\frac{q\pi}{\arcsin \left ( \frac{1}{2}\sin \left ( \frac{q\pi }{2} \right ) \right )}
which for q=2n gives q/m is an integer.
Is there a more elegant general solution?

Thanks!
 
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Are q and m integers?
 
In general, for my purpose, both are continuous.
 
You found an expression of m as function of q. What else do you need?
You can add +2 pi * k at a suitable place (where you take the arcsine) to get the other solutions for m.
 
I'm in doubt if there is a simpler expression involving q,m,π and probably n (integer). Without trigonometric functions.
 
That would surprise me.
 
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