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.
New in 1
New to Mathematica? Find your learning path »
Have a question? Ask support »