ExactNumberQ[expr] returns True if expr is an exact real or complex number, and returns False otherwise.
ExpandDenominator[expr] expands out products and powers that appear as denominators in expr.
ExponentFunction is an option for NumberForm and related functions that determines the exponent to use in printing approximate real numbers.
Exponent[expr, form] gives the maximum power with which form appears in the expanded form of expr. Exponent[expr, form, h] applies h to the set of exponents with which form ...
ExtremeValueDistribution[\[Alpha], \[Beta]] represents an extreme value distribution with location parameter \[Alpha] and scale parameter \[Beta].
FaceGrids is an option for three-dimensional graphics functions that specifies grid lines to draw on the faces of the bounding box.
FactorSquareFree[poly] pulls out any multiple factors in a polynomial.
FortranForm[expr] prints as a Fortran language version of expr.
FourierParameters is an option to Fourier and related functions that specifies the conventions to use in computing Fourier transforms.
FromCharacterCode[n] gives a string consisting of the character with integer code n. FromCharacterCode[{n_1, n_2, ...}] gives a string consisting of the sequence of ...