Is the Z-Transform of sin(Bn) Really Zero?

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Homework Statement



I'm trying to take the (two-sided, aka defined for all n) Z-transform of

[tex]x(n)=sin(Bn)[/tex]

Homework Equations

The Attempt at a Solution



What I tried to do was split x(n) into

[tex]x(n)=sin(Bn)u(n)+sin(Bn)u(-n-1)[/tex]

The Z transform of the first part of x(n) was found from a table. The z transform of the 2nd was found from the fact that the z transform of [tex]-sin(Bn)u(-n-1)[/tex] equals the z transform of [tex]sin(Bn)u(n)[/tex]

[tex]X(z)=\frac{z sin(B)}{z^2-2zcos(B)+1}-\frac{z sin(B)}{z^2-2zcos(B)+1}[/tex]

So the z transform is zero? Could this be?
 
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