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Give Some Information on : Power Set
@Muskan @abhi_abhi @electrokid
In mathematics, the power set (or powerset) of any set S, written , P(S), ℙ(S) ℘(S) or 2S, is the set of all subsets of S, including the empty set and S itself. In axiomatic set theory (as developed, for example, in the ZFC axioms), the existence of the power set of any set is postulated by the axiom of power set.
he power set of {1,2,3,4} is {{}, {1}, {2}, {1,2}, {3}, {1,3}, {2,3}, {1,2,3}, {4}, {1,4}, {2,4}, {1,2,4}, {3,4}, {1,3,4}, {2,3,4}, {1,2,3,4}}.
you just copied and pasted wiki
i am just reading it now
If we have a set {a,b,c}: Then a subset of it could be {a} or {b}, or {a,c}, and so on, And {a,b,c} is also a subset of {a,b,c} (yes, that's true, but its not a "proper subset") And the empty set {} is also a subset of {a,b,c} In fact, if you list all the subsets of S={a,b,c} you will have the Power Set of {a,b,c}: P(S) = { {}, {a}, {b}, {c}, {a, b}, {a, c}, {b, c}, {a, b, c} } Think of it as all the different ways you can select the items (the order of the items doesn't matter), including selecting none, or all.