Numerator

Numerator[expr]
gives the numerator of expr.

Details and OptionsDetails and Options

  • Numerator picks out terms which do not have superficially negative exponents. Denominator picks out the remaining terms.
  • An exponent is "superficially negative" if it has a negative number as a factor.
  • The standard representation of rational expressions as products of powers means that you cannot simply use Part to extract numerators.
  • Numerator can be used on rational numbers.

ExamplesExamplesopen allclose all

Basic Examples  (1)Basic Examples  (1)

Extract the numerator of a rational number:

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Extract the numerator of a rational expression:

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Introduced in 1988
(1.0)