enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Quadratic equation - Wikipedia

    en.wikipedia.org/wiki/Quadratic_equation

    A lesser known quadratic formula, as used in Muller's method, provides the same roots via the equation =. This can be deduced from the standard quadratic formula by Vieta's formulas, which assert that the product of the roots is c/a.

  3. Møller–Plesset perturbation theory - Wikipedia

    en.wikipedia.org/wiki/Møller–Plesset...

    Møller–Plesset perturbation theory (MP) is one of several quantum chemistry post-Hartree–Fock ab initio methods in the field of computational chemistry.It improves on the Hartree–Fock method by adding electron correlation effects by means of Rayleigh–Schrödinger perturbation theory (RS-PT), usually to second (MP2), third (MP3) or fourth (MP4) order.

  4. Darcy friction factor formulae - Wikipedia

    en.wikipedia.org/wiki/Darcy_friction_factor_formulae

    If more than one formula is applicable in the flow regime under consideration, the choice of formula may be influenced by one or more of the following: Required accuracy; Speed of computation required; Available computational technology: calculator (minimize keystrokes) spreadsheet (single-cell formula) programming/scripting language (subroutine).

  5. Spearman–Brown prediction formula - Wikipedia

    en.wikipedia.org/wiki/Spearman–Brown_prediction...

    The Spearman–Brown prediction formula, also known as the Spearman–Brown prophecy formula, is a formula relating psychometric reliability to test length and used by psychometricians to predict the reliability of a test after changing the test length. [1] The method was published independently by Spearman (1910) and Brown (1910). [2] [3]

  6. Unbiased estimation of standard deviation - Wikipedia

    en.wikipedia.org/wiki/Unbiased_estimation_of...

    Correction factor versus sample size n.. When the random variable is normally distributed, a minor correction exists to eliminate the bias.To derive the correction, note that for normally distributed X, Cochran's theorem implies that () / has a chi square distribution with degrees of freedom and thus its square root, / has a chi distribution with degrees of freedom.

  7. Water vapor - Wikipedia

    en.wikipedia.org/wiki/Water_vapor

    Water vapor reflects radar to a lesser extent than do water's other two phases. In the form of drops and ice crystals, water acts as a prism, which it does not do as an individual molecule; however, the existence of water vapor in the atmosphere causes the atmosphere to act as a giant prism. [49]

  8. Logarithm - Wikipedia

    en.wikipedia.org/wiki/Logarithm

    The logarithm log b x can be computed from the logarithms of x and b with respect to an arbitrary base k using the following formula: [nb 2] ⁡ = ⁡ ⁡. Typical scientific calculators calculate the logarithms to bases 10 and e. [5]

  9. Green chemistry metrics - Wikipedia

    en.wikipedia.org/wiki/Green_chemistry_metrics

    The formula also fails to address the level of toxicity associated with a process. Until all toxicology data is available for all chemicals and a term dealing with these levels of “benign” reagents is written into the formula, the effective mass efficiency is not the best metric for chemistry.