Veksel utregning

[math]\left ( \frac{1}{2} \right )[/math]

[math](r+x)^2+(R-x)^2-(R-r)^2-2(r+x)(R-x) cos(\alpha)=0[/math]
[math]R(r(1-cos(\alpha))-x(1+cos(\alpha))) + x\cdot(1+cos(\alpha))(r+x)=0[/math]
[math]R\left (r\cdot \left ( \frac{1-cos(\alpha)}{1+cos(\alpha)} \right )-x \right )+x\cdot(r+x)=0[/math]

[math](1-cos(\alpha)[/math]