概率论提高二维随机变量probability-statistics-1:概率论:18:第十八章多维随机变量及其分布:综合题:一-选择题:2:80:1概率统计做题本（一）解答版选择题不看本题本题讨论已掌握查看解析收入错题#8966设二维随机变量 (X1,X2)\left({{X}_{1},{X}_{2}}\right)(X1,X2) 的概率密度为 f1(x1,x2),Y1=2X1,Y2=3X2{f}_{1}\left({{x}_{1},{x}_{2}}\right),{Y}_{1} = 2{X}_{1},{Y}_{2} = 3{X}_{2}f1(x1,x2),Y1=2X1,Y2=3X2，则 (Y1,Y2)\left({{Y}_{1},{Y}_{2}}\right)(Y1,Y2) 的概率密度 f2(y1,y2)=( ).{f}_{2}\left({{y}_{1},{y}_{2}}\right) = \left(\;\right).f2(y1,y2)=().A. f1(2y1,3y2){f}_{1}\left({2{y}_{1},3{y}_{2}}\right)f1(2y1,3y2)B. f1(12y1,13y2){f}_{1}\left({\frac{1}{2}{y}_{1},\frac{1}{3}{y}_{2}}\right)f1(21y1,31y2)C. 12f1(2y1,3y2)\frac{1}{2}{f}_{1}\left({2{y}_{1},3{y}_{2}}\right)21f1(2y1,3y2)D. 16f1(12y1,13y2)\frac{1}{6}{f}_{1}\left({\frac{1}{2}{y}_{1},\frac{1}{3}{y}_{2}}\right)61f1(21y1,31y2)