Construct the envelope of the light rays emitted from a radiant point source at the circumference after
reflection by the same circle.

> restart;

> m:=[[-1,sin(t)],[cos(t),sin(t)],[cos(t)-cos(3*t/2),sin(t)-sin(3*t/2)]]:

> t:=k*Pi/50-Pi:

> plot([m$k=0..100],color=yellow,scaling=constrained,axes=none);

>