Power set
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Revision as of 17:47, 12 February 2015 by Alec (Talk | contribs) (Created page with "The power set of a set <math>X</math> is denoted by <math>\mathcal{P}(X)</math>, sometimes <math>2^X</math> (a number to the power of a set is not defined (as it cannot be use...")
The power set of a set X is denoted by P(X), sometimes 2X (a number to the power of a set is not defined (as it cannot be usefully defined) leaving it free to be used as notation. This comes from the cardinality of the power set being 2|X|)
The characteristic property of the power set is that ∀U⊂X:U∈P(X)
It is the set of all subsets of X
