p_(1)+p_(2)+p_(3)+p_(4)=1
p_(1)+0,2+0,3+0,1=1
p_(1)=1-0,2-0,3-0,1=0,4
M(X)=x_(1)*p_(1)+x_(2)*p_(2)+x_(3)*p_(3)+x_(4)*p_(4)
2,6=1*0,4+2*0,2+x_(3)*0,3+x_(4)*0,1
D(X)=M(X^2)-(M(X))^2
2,84=M(X^2)-2,6^2
M(X^2)=2,84+2,6^2
M(X^2)=x^2_(1)*p_(1)+x^2_(2)*p_(2)+x^2_(3)*p_(3)+x^2_(4)*p_(4)
2,84+2,6^2=1^2*0,4+2^2*0,2+x^2_(3)*0,3+x^2_(4)*0,1
Из системы уравнений:
2,6=1*0,4+2*0,2+x_(3)*0,3+x_(4)*0,1
2,84+2,6^2=1^2*0,4+2^2*0,2+x^2_(3)*0,3+x^2_(4)*0,1
найдем x_(3) и x_(4)