enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Optimum HDTV viewing distance - Wikipedia

    en.wikipedia.org/wiki/Optimum_HDTV_viewing_distance

    Range recommendations from manufacturers are the most modest of the groupings. For the minimum (or nearest) viewing distance, they recommend a view angle of approximately 31 degrees; and for the maximum, a view angle as low as 10 degrees. [35] [36] A 10-degree view angle is approximately the angle that NTSC television was typically viewed from ...

  3. Davenport chained rotations - Wikipedia

    en.wikipedia.org/wiki/Davenport_chained_rotations

    Any extrinsic rotation is equivalent to an intrinsic rotation by the same angles but with inverted order of elemental rotations, and vice versa. For instance, the intrinsic rotations x-y’-z″ by angles α, β, γ are equivalent to the extrinsic rotations z-y-x by angles γ, β, α. Both are represented by a matrix

  4. Rotation matrix - Wikipedia

    en.wikipedia.org/wiki/Rotation_matrix

    To find the angle of a rotation, once the axis of the rotation is known, select a vector v perpendicular to the axis. Then the angle of the rotation is the angle between v and Rv. A more direct method, however, is to simply calculate the trace: the sum of the diagonal elements of the rotation matrix.

  5. Focal length - Wikipedia

    en.wikipedia.org/wiki/Focal_length

    A lens with a focal length about equal to the diagonal size of the film or sensor format is known as a normal lens; its angle of view is similar to the angle subtended by a large-enough print viewed at a typical viewing distance of the print diagonal, which therefore yields a normal perspective when viewing the print; [9] this angle of view is ...

  6. Straightedge and compass construction - Wikipedia

    en.wikipedia.org/wiki/Straightedge_and_compass...

    Angle trisection is the construction, using only a straightedge and a compass, of an angle that is one-third of a given arbitrary angle. This is impossible in the general case. For example, the angle 2 π /5 radians (72° = 360°/5) can be trisected, but the angle of π /3 radians (60°) cannot be trisected. [8]

  7. Mathematics - Wikipedia

    en.wikipedia.org/wiki/Mathematics

    For larger scales the sum of the angles of a triangle is not equal to 180°. Geometry is one of the oldest branches of mathematics. It started with empirical recipes concerning shapes, such as lines, angles and circles, which were developed mainly for the needs of surveying and architecture, but has since blossomed out into many other subfields ...

  8. Angle - Wikipedia

    en.wikipedia.org/wiki/Angle

    The supplement of an interior angle is called an exterior angle; that is, an interior angle and an exterior angle form a linear pair of angles. There are two exterior angles at each vertex of the polygon, each determined by extending one of the two sides of the polygon that meet at the vertex; these two angles are vertical and hence are equal.

  9. Symmetry (geometry) - Wikipedia

    en.wikipedia.org/wiki/Symmetry_(geometry)

    A drawing of a butterfly with bilateral symmetry, with left and right sides as mirror images of each other.. In geometry, an object has symmetry if there is an operation or transformation (such as translation, scaling, rotation or reflection) that maps the figure/object onto itself (i.e., the object has an invariance under the transform). [1]