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Documentation / Mathematica / Built-in Functions / Algebraic Computation / Formula Manipulation /

Numerator

FilledSmallSquare Numerator[expr] gives the numerator of expr.

FilledSmallSquare Numerator picks out terms which do not have superficially negative exponents. Denominator picks out the remaining terms.

FilledSmallSquare An exponent is "superficially negative" if it has a negative number as a factor.

FilledSmallSquare The standard representation of rational expressions as products of powers means that you cannot simply use Part to extract numerators.

FilledSmallSquare Numerator can be used on rational numbers.

FilledSmallSquare See Section 1.4.7.

FilledSmallSquare See also: ExpandNumerator.

FilledSmallSquare New in Version 1.

Further Examples