X∼b(1,p)
x∈{ 0 , 1 }
p(x)=px(1−p)1−x
F(x)=(1−p)1−x
E(X)=p
Var(X)=p(1−p)
γ 1=1−2p√p(1−p)=q−p√pq
γ 2=6p2−6p+1p(1−p)=1−6pqpq
ϕ (t)=1+p(eit−1)