MATH 6118-090
Non-euclidean Geometry
Exercise Set #6
1. What
is the distance between the points
and
in the Poincaré upper half plane, H? Remember that the Poincaré
upper half plane has a non-euclidean arclength element, so the answer is not 4.
2. What
is the distance between the points
and
in the Poincaré upper half plane, H?
3. Prove that the dilation
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preserves the Poincaré arclength element.
4. Let
and
. Find M and
N, the endpoints of the Poincaré line through P and Q.
5. Let
and
. Find M and
N, the endpoints of the Poincaré line through P and Q.
6. Show that the map

Is inversion in the circle with radius r and centered at the origin, O.
7. Let
be a line with
equation
with
. Show
that the image of
under the action of
gives the equation
of a circle which passes through O.