enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Wikipedia:Reference desk/Archives/Mathematics/2007 November 1 ...

    en.wikipedia.org/wiki/Wikipedia:Reference_desk/...

    If it helps any, here are the problem and the answers the author and I got: The ellipse (x^2 / a^2) + (y^2 / b^2) = 1, a > b is rotated about the x-axis to form a surface called an ellipsoid. Find the surface area of this ellipsoid.

  3. Rotation of axes in two dimensions - Wikipedia

    en.wikipedia.org/wiki/Rotation_of_axes_in_two...

    For example, to study the equations of ellipses and hyperbolas, the foci are usually located on one of the axes and are situated symmetrically with respect to the origin. If the curve (hyperbola, parabola , ellipse, etc.) is not situated conveniently with respect to the axes, the coordinate system should be changed to place the curve at a ...

  4. Elliptic curve - Wikipedia

    en.wikipedia.org/wiki/Elliptic_curve

    Graphs of curves y 2 = x 3 − x and y 2 = x 3 − x + 1. Although the formal definition of an elliptic curve requires some background in algebraic geometry, it is possible to describe some features of elliptic curves over the real numbers using only introductory algebra and geometry.

  5. Prolate spheroidal wave function - Wikipedia

    en.wikipedia.org/wiki/Prolate_spheroidal_wave...

    In mathematics, prolate spheroidal wave functions are eigenfunctions of the Laplacian in prolate spheroidal coordinates, adapted to boundary conditions on certain ellipsoids of revolution (an ellipse rotated around its long axis, “cigar shape“).

  6. Elliptic coordinate system - Wikipedia

    en.wikipedia.org/wiki/Elliptic_coordinate_system

    The classic applications of elliptic coordinates are in solving partial differential equations, e.g., Laplace's equation or the Helmholtz equation, for which elliptic coordinates are a natural description of a system thus allowing a separation of variables in the partial differential equations. Some traditional examples are solving systems such ...

  7. Rytz's construction - Wikipedia

    en.wikipedia.org/wiki/Rytz's_construction

    The Rytz’s axis construction is a basic method of descriptive geometry to find the axes, the semi-major axis and semi-minor axis and the vertices of an ellipse, starting from two conjugated half-diameters. If the center and the semi axis of an ellipse are determined the ellipse can be drawn using an ellipsograph or by hand (see ellipse).

  8. Ellipsoid - Wikipedia

    en.wikipedia.org/wiki/Ellipsoid

    Plane section of the unit sphere (see example) Solution: The scaling u = ⁠ x / a ⁠, v = ⁠ y / b ⁠, w = ⁠ z / c ⁠ transforms the ellipsoid onto the unit sphere u 2 + v 2 + w 2 = 1 and the given plane onto the plane with equation + + =. Let m u u + m v v + m w w = δ be the Hesse normal form of the new plane and

  9. Oblate spheroidal coordinates - Wikipedia

    en.wikipedia.org/wiki/Oblate_spheroidal_coordinates

    since they are ellipses rotated about the z-axis, which separates their foci. An ellipse in the x-z plane (Figure 2) has a major semiaxis of length a cosh μ along the x-axis, whereas its minor semiaxis has length a sinh μ along the z-axis. The foci of all the ellipses in the x-z plane are located on the x-axis at ±a.