• Alias: dd.
• Compound operator with built-in evaluation rules.
• can only be interpreted by default when it appears with or other integral operators.
• f x is by default interpreted as Integrate[f, x].
• \[DifferentialD] is also used in TraditionalForm to indicate total derivatives.
• See Section 1.10.4, Section 1.10.4, Section 3.10.1, Section 3.10.3 and Section 3.10.4.
• See also: \[PartialD] , \[CapitalDifferentialD] , \[Delta] .