Generalités

A,B U
A B A∩B={e∈ U | e∈ A e∈ B}
A B A ∪ B ={e∈ U | e∈ A e∈ B}
A B A \ B ={e∈ U | e∈ A e /∈ B}
AA=U \ A ={e∈ U | e /∈ A}
P(A)A
A∪B =A ∩ B A ∩ B =A ∪ B
nA1. . . An
nA1×. . . × An={(a1, . . . , an)|ai∈ Ai}
Ai=AiAnA1×. . . × An

A1. . . An
A1×. . . × An
R⊆ A × A
R x ∈ A (x, x)∈R R
x∈ A (x, x)/∈R
R x, y ∈ A (x, y)∈R
(y, x)∈R R x, y ∈ A
(x, y)∈R(y, x)∈R x =y
≥
>
=
≤

R x, y, z ∈ A (x, y)∈ A
(y, z)∈R(x, z)∈R
R
R f R
f a1Rb1. . . anRbn
f(a1, . . . , an)Rf(b1. . . bn)
⊆
=

a∈ A R
[a]R={b∈ A | aRb}