NotElement 
NotElement[x,dom]
or x∉dom asserts that is not an element of the domain dom.
NotElement[x1…xn,dom]
asserts that none of the are elements of dom.
NotElement[patt,dom]
asserts that any expression matching the pattern patt is not an element of the domain dom.
Details
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- x∉dom can be entered as
!el
dom or x∖[NotElement]dom.
- NotElement[x,dom] is equivalent to Not[Element[x, dom]].
- NotElement[x1…xn,dom] is equivalent to Not[Element[x1,dom]]&&…&&Not[Element[xn,dom]].
Examples
open allclose allBasic Examples (3)
Properties & Relations (1)
For a single variable, the negation of NotElement is automatically converted to Element:
For multiple variables the negation of NotElement is not automatically simplified:
Use LogicalExpand to find the representation in terms of Element:
Text
Wolfram Research (2007), NotElement, Wolfram Language function, https://reference.wolfram.com/language/ref/NotElement.html.
CMS
Wolfram Language. 2007. "NotElement." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/NotElement.html.
APA
Wolfram Language. (2007). NotElement. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/NotElement.html