
Re: Cross Ratio of Four Concurrent Lines
Posted:
Jul 1, 2013 3:33 PM


> Hi Narasimham, > > the problem is very interesting. I studied the > special case A=[1 0], B=[0 1], C=[1 0], D=[0 1], > where point P is element of the box [2 2]x[2 2], > and tet=angle(APB), phi=angle(BPC), psi=angle(CPD). > For the Cross Ratio we have > > CR=sin(tet+phi)*sin(phi+psi)/(sin(tet+phi+psi)*sin(phi > )). > > The result is shown in the attachment. > > Best regards, > Avni
Hi Avni,
May be you like to sketch a few line loci inside the red area for some particular CR values.
Best Regards, Narasimham

