# Rearrange $y = \frac{\tan\left(\frac{N x}{2}\right)}{N}$ to give N

Is it possible to rearrange

$$y = \frac{ \tan \left(\frac{N x}{2}\right)}{N}$$

where $x \lt \pi$ as a function of x and y that gives N?

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What do you mean here by "rearrange"? I don't think there is a way to write the right-hand side that's any simpler than what you already have. – Greg Martin Jan 9 '13 at 6:11
I mean to give N as a function of x and y. – geometrikal Jan 11 '13 at 3:43
The program "maple" could not solve for N as a function of x,y. – coffeemath Jan 11 '13 at 6:41
Agreed, even the special case $\tan(N)/N = 1$ doesn't admit a closed-form solution, I believe. – Greg Martin Jan 11 '13 at 21:21
Thankyou all ... i will have to come up with an approximation. – geometrikal Jan 12 '13 at 0:05