Involution
Revision as of 19:29, 19 September 2008 by Herefishyfishy1 (talk | contribs)
An involution is a function whose inverse is itself.
Examples
- The function
has the inverse
, which is the same function, and thus
is an involution.
- The logical NOT is an involution because $\neg \neg p} \equiv p$ (Error compiling LaTeX. Unknown error_msg).
- The additive negation is an involution because
.
- The multiplicative inverse is an involution because
. In fact, for any
,
is an involution.
Properties
- An function is an involution iff it is symmetric about the line
in the coordinate plane.