(1-0.6) * (1-x) =1-0.92
X=0.8
(2)P(Y=0)= 1-0.92=0.08
P(Y=2)=0.48 입니다
P(Y= 1)=0.44
Y = 0 * 0.08+1* 0.44+2 * 0.48 =1.4
Y 2 = 0 2 * 0.08+12 * 0.44+2 2 * 0.48 = 2.36
분산 = y 2-(y) 2 = 2.36-1.4 2 = 0.4.