enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Partial derivative - Wikipedia

    en.wikipedia.org/wiki/Partial_derivative

    Partial derivatives appear in thermodynamic equations like Gibbs-Duhem equation, in quantum mechanics as in Schrödinger wave equation, as well as in other equations from mathematical physics. The variables being held constant in partial derivatives here can be ratios of simple variables like mole fractions x i in the following example ...

  3. ∂ - Wikipedia

    en.wikipedia.org/wiki/%E2%88%82

    The symbol was introduced originally in 1770 by Nicolas de Condorcet, who used it for a partial differential, and adopted for the partial derivative by Adrien-Marie Legendre in 1786. [3] It represents a specialized cursive type of the letter d , just as the integral sign originates as a specialized type of a long s (first used in print by ...

  4. Partial differential equation - Wikipedia

    en.wikipedia.org/wiki/Partial_differential_equation

    In mathematics, a partial differential equation (PDE) is an equation which involves a multivariable function and one or more of its partial derivatives.. The function is often thought of as an "unknown" that solves the equation, similar to how x is thought of as an unknown number solving, e.g., an algebraic equation like x 2 − 3x + 2 = 0.

  5. Triple product rule - Wikipedia

    en.wikipedia.org/wiki/Triple_product_rule

    Define p 2 as the point at time t whose x-coordinate matches that of p̄ 1, and define p̄ 2 to be the corresponding point of p 2 as shown in the figure on the right. The distance Δx between p 1 and p̄ 1 is the same as the distance between p 2 and p̄ 2 (green lines), and dividing this distance by Δt yields the speed of the wave.

  6. First-order partial differential equation - Wikipedia

    en.wikipedia.org/wiki/First-order_partial...

    In mathematics, a first-order partial differential equation is a partial differential equation that involves the first derivatives of an unknown function of variables. The equation takes the form [ 1 ] F ( x 1 , … , x n , u , u x 1 , … u x n ) = 0 , {\displaystyle F(x_{1},\ldots ,x_{n},u,u_{x_{1}},\ldots u_{x_{n}})=0,} using subscript ...

  7. Wave equation - Wikipedia

    en.wikipedia.org/wiki/Wave_equation

    The wave equation is a second-order linear partial differential equation for the description of waves or standing wave fields such as mechanical waves (e.g. water waves, sound waves and seismic waves) or electromagnetic waves (including light waves).

  8. Vector calculus identities - Wikipedia

    en.wikipedia.org/wiki/Vector_calculus_identities

    Euler's formula; Partial fractions ... [1] [2] Less general but ... Similar rules apply to algebraic and differentiation formulas. For algebraic formulas one may ...

  9. Laplace's equation - Wikipedia

    en.wikipedia.org/wiki/Laplace's_equation

    In mathematics and physics, Laplace's equation is a second-order partial differential equation named after Pierre-Simon Laplace, who first studied its properties.This is often written as = or =, where = = is the Laplace operator, [note 1] is the divergence operator (also symbolized "div"), is the gradient operator (also symbolized "grad"), and (,,) is a twice-differentiable real-valued function.