When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. List of uniform polyhedra by vertex figure - Wikipedia

    en.wikipedia.org/wiki/List_of_uniform_polyhedra...

    Wythoff symbols are written p|q r, p q|r, p q r| where the spherical triangle has angles π/p,π/q,π/r, the bar indicates the position of the vertices in relation to the triangle. Example vertex figures. Johnson (2000) classified uniform polyhedra according to the following: Regular (regular polygonal vertex figures): p q, Wythoff symbol q|p 2

  3. Tetrahedron - Wikipedia

    en.wikipedia.org/wiki/Tetrahedron

    Its vertex–center–vertex angle—the angle between lines from the tetrahedron center to any two vertices—is ⁡ = ⁡ (), denoted the tetrahedral angle. [9] It is the angle between Plateau borders at a vertex. Its value in radians is the length of the circular arc on the unit sphere resulting from centrally projecting one edge of the ...

  4. Quadrilateral - Wikipedia

    en.wikipedia.org/wiki/Quadrilateral

    The following two formulas express the area in ... (x 1,y 1) and BD as (x 2,y 2), ... the x and y coordinates of the vertex centroid are the arithmetic means of the x ...

  5. Circumconic and inconic - Wikipedia

    en.wikipedia.org/wiki/Circumconic_and_inconic

    A point in the interior of a triangle is the center of an inellipse of the triangle if and only if the point lies in the interior of the triangle whose vertices lie at the midpoints of the original triangle's sides. [3]: p.139 For a given point inside that medial triangle, the inellipse with its center at that point is unique. [3]: p.142

  6. Mixtilinear incircles of a triangle - Wikipedia

    en.wikipedia.org/wiki/Mixtilinear_incircles_of_a...

    The three lines joining a vertex to the point of contact of the circumcircle with the corresponding mixtilinear incircle meet at the external center of similitude of the incircle and circumcircle. [3] The Online Encyclopedia of Triangle Centers lists this point as X(56). [6]

  7. Trilinear coordinates - Wikipedia

    en.wikipedia.org/wiki/Trilinear_coordinates

    In geometry, the trilinear coordinates x : y : z of a point relative to a given triangle describe the relative directed distances from the three sidelines of the triangle. Trilinear coordinates are an example of homogeneous coordinates .

  8. Incircle and excircles - Wikipedia

    en.wikipedia.org/wiki/Incircle_and_excircles

    The trilinear coordinates for a point in the triangle is the ratio of all the distances to the triangle sides. Because the incenter is the same distance from all sides of the triangle, the trilinear coordinates for the incenter are [ 6 ] 1 : 1 : 1. {\displaystyle \ 1:1:1.}

  9. Modern triangle geometry - Wikipedia

    en.wikipedia.org/wiki/Modern_triangle_geometry

    A real-valued function f of three real variables a, b, c may have the following properties: Homogeneity: f(ta,tb,tc) = t n f(a,b,c) for some constant n and for all t > 0. Bisymmetry in the second and third variables: f(a,b,c) = f(a,c,b). If a non-zero f has both these properties it is called a triangle center function.