This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.

# Element ()

 Element[x, dom]or xdom asserts that x is an element of the domain dom. Element[{x1, x2, ...}, dom]asserts that all the xi are elements of dom. Element[patt, dom]asserts that any expression matching the pattern patt is an element of dom.
• xdom can be entered as x Esc el Esc dom or x\[Element]dom.
• Element can be used to set up assumptions in Simplify and related functions.
• Possible domains are:
 Algebraics algebraic numbers Booleans Complexes complex numbers Integers integers Primes prime numbers Rationals rational numbers Reals real numbers
• xdom if possible evaluates immediately when x is numeric.
• (x1|x2|...)dom is equivalent to {x1, x2, ...}dom.
• {x1, x2, ...}dom evaluates to (x1|x2|...)dom if its truth or falsity cannot immediately be determined.
Test whether is an element of the reals:
 Out[1]=

Express domain membership for an expression:
 Out[1]=

Enter using Esc elem Esc:
 Out[1]=
 Scope   (6)