Calcul du rayon de la sphère inscrite dans le tétraèdre
Calibration of an ellipse's algebraic equation and direct determination of its parameters.
Certain equalities and inequalities concerning polygons in .
Certain inequalities concerning bicentric quadrilaterals, hexagons and octagons.
Certain inequalities concerning some kinds of chordal polygons.
Ceva-Dreiecke.
Ceva's and Menelaus' theorems for the -dimensional space.
Cevians as sides of triangles.
Charakteristiken und Schnittzahlformeln für p-l-s-Kegelschnitte
Chiral Polytopes from Hyperbolic Honeycombs.
Chord-decreasing homeomorphisms in Euclidean spaces
Chords and arclength of a closed space curve
Circle packing in the hyperbolic plane.
Circumcenter, Circumcircle and Centroid of a Triangle
We introduce, using the Mizar system [1], some basic concepts of Euclidean geometry: the half length and the midpoint of a segment, the perpendicular bisector of a segment, the medians (the cevians that join the vertices of a triangle to the midpoints of the opposite sides) of a triangle. We prove the existence and uniqueness of the circumcenter of a triangle (the intersection of the three perpendicular bisectors of the sides of the triangle). The extended law of sines and the formula of the radius...
Classes of Graphs Which Approximate the Complete Euclidean Graph.
Classical -symbols and the tetrahedron.
Classification of dodecahedral space forms.
Classification of hyperbolic dodecahedron tilings of maximally face-transitive motion groups. (Klassifikation der hyperbolischen Dodekaederpflasterungen von maximalen flächentransitiven Bewegungsgruppen.)
Čo s nejednoznačným zadaním slovnej úlohy?
In the paper we deal with a task about two circles touching in a rectangle. The assignment of the task was formulated in a fuzzy way, so solvers understood it differently. We present extracts from the authentic solutions which reflect this phenomenon. We suggest an approach to such tasks, how to solve them and how to assess their solutions.
Cobordism of automorphisms of surfaces