Sous-ensembles : Intersection, Union, Complémentaire

A,B A B
A B A ⊂B
A⊂B⇔ ∀x(x∈A⇒x∈B)
A B A
B

A∅ ⊂ A A ⊂A
A={,,,}B={,}B⊂A

EP(E)E
A={,,} P(A)

A
∅,{ },{ },{ },{,},{,},{,},{,,}
P(E) = {∅,{ },{ },{ },{,},{,},{,},{, , }}