Nombres complexes

a, b c
(E) : z3+az2+bz +c= 0
Z(E)
|Z| ≤ max(1,|a|+|b|+|c|)
r > 0|Z| ≤ max r, |a|+|b|
r+|c| r2
(E0) : x3− |a|x2− |b|x− |c|= 0 ρR∗
+
|Z| ≤ ρ
n
A1A2...AnG
B1, B2, ..., Bn(A1G)
(A2G) (AnG)
A1G
GB1
+A2G
GB2
+... +AnG
GBn
=n
Um={e2ikπ
m/0≤k≤m−1}
m
z zm= 1
n f :U2n→U2n
f(f(z)) = z2z U2n
{z2/z ∈U2n}UnU2n
f
f(z2) = (f(z))2z U2n
f(z) = f(z0)⇒z=z0z=−z0f(1) = f(−1) = 1
n z U2nz2=−1
f
n z U2nz3= 1 z6= 1
f
n
g Unz Unz2
f
φ:Un→Unφ◦φ=g f
n= 5
n= 7 n= 9