proper subset

Let $S$ be a set and let $X\subset S$ be a subset. We say $X$ is a proper subset of $S$ if $X\ne S$.

Title	proper subset
Canonical name	ProperSubset
Date of creation	2013-03-22 11:53:28
Last modified on	2013-03-22 11:53:28
Owner	djao (24)
Last modified by	djao (24)
Numerical id	7
Author	djao (24)
Entry type	Definition
Classification	msc 03E20
Classification	msc 03B22
Classification	msc 03-00
Classification	msc 03-01