I have the following functions defined:
var('k,j,N')
s(k)=sin(4*pi*k/N)*sin(2*pi/N*(k+1))*sin(2*pi/N*(k-1))
w(k)=(sin(2*pi/N*(k-1))/sin(2*pi/N*k)*sin(4*pi/N))*sin(2*pi/N)
AA(N,j,k)=s(k)+s(j)+sin(2*pi*6/N)*sin(2*pi*2/N)/(sin(2*pi*3/N)*sin(2*pi/N))*(w(k)+w(j))-sin(4*pi*2/N)*sin(2*2*pi/N)/sin(2*pi/N)*(w(k)*w(j))-sin(2*pi*6/N)*sin(2*pi*2/N)/(sin(2*pi*3/N)*sin(2*pi/N))
assume(j>1,k>1,N>8*(j+k+1),N>10)
Now, if I use the solve function:
sage: solve(AA(N,j,k)==0,N)
I get the output
[sin(4*pi*k/N) == (sin(8*pi/N)*sin(6*pi/N)*sin(4*pi/N)^3*sin(2*pi/N)^2*sin(-2*(pi
- pi*j)/N)*sin(-2*(pi - pi*k)/N) - sin(2*pi*j/N)*sin(12*pi/N)*sin(4*pi/N)^2*sin(2*pi/N)*sin(-2*(pi
- pi*k)/N) - (sin(4*pi*j/N)*sin(2*pi*j/N)*sin(6*pi/N)*sin(2*pi/N)*sin(2*(pi
+ pi*j)/N)*sin(-2*(pi - pi*j)/N) + sin(12*pi/N)*sin(4*pi/N)^2*sin(2*pi/N)*sin(-2*(pi
- pi*j)/N) - sin(2*pi*j/N)*sin(12*pi/N)*sin(4*pi/N))*sin(2*pi*k/N))/(sin(2*pi*j/N)*sin(2*pi*k/N)*sin(6*pi/N)*sin(2*pi/N)*sin(2*(pi
+ pi*k)/N)*sin(-2*(pi - pi*k)/N))]
However, it is my hope that this equation has no solutions. Indeed, if I add to the assumption that AA(N,j,k)>0, I obtain a contradiction (inconsistent assumptions), but if I add AA(N,j,k)==0, I don't get inconsistent assumptions.
Is there a way to check if this is a floating point error, or if there really is a solution with my assumptions?
