Partiel de Probabilités

A B
P(A) = PB(A)P(B) + PBc(A)P(Bc).
p∈]0,1[ p
1−p
p
p
n1
n
A=
9/10
7
n≥ln(10)
ln(49) −ln(48).
15 q6= 1 n0, n n0≤n
(1 −q)
n
X
k=n0
qk=qn0(1 −qn−n0+1)

q∈]0,1[ X q
k≥1
P(X=k) = q(1 −q)k−1.
(pk=q(1 −q)k−1, k ≥1)
N?
15
X
X X
Y
Y Y
[|1,15|]k∈[|1,15|]P(Y=k) = 1
15
n∈N?Pn
k=1 k=n(n+1)
2Y
p1
p
NA
PA(p)P(NA≥2) NA
(3, p)PA(p).
ND(4, q)
PD(q)
PD(q) = q2(3q2−8q+ 6).
p=q p 7→ PA(p)−PD(p)