设二维随机变量(x y)的概率密度为f(x,y)={2,0<=x<=1,0<=y<=x, 0...答:2018-01-09 设随机变量X-N(0 1)求Y=e^x概率密度? 1 2014-11-20 设二维随机变量(X,Y)的概率密度为:f(x,y)=[cx^... 101 2014-12-22 设二维连续型随机变量(X,Y)具有概率密度f(x,y)=2,... 3 2011-12-09 设二维随机变量(X,Y)的概率密度为f(x,y)={c(x+... 2 2014-07-19 ...
已知二维随机变量联合密度求概率答:解:(1),利用概率密度函数的性质,有∫(-∞,∞)∫(-∞,∞)f(x,y)dxdy=1,∴k∫(0,1)∫(0,1)(x+y)dxdy=1。而,∫(0,1)(x+y)dy=x+1/2,∴k∫(0,1)(x+1/2)dx=1,k=1。(2),P(x<1/2,y<1/2)=∫(0,1/2)∫(0,1/2)(x+y)dxdy=∫(0,1/2)(x/2+1/8...
设二维随机变量(X,Y)的概率密度为f(x,y)=2,0≤x≤1,0≤y≤;0,其他;求...答:2014-11-06 设二维随机变量(X,Y)具有联合概率密度f(x,y)={c(... 2012-01-10 设二维随机变量(X,Y)的概率密度为f (x,y)=6x,0... 2016-05-27 设二维随机变量(X,Y)服从区域D={(x,y)|0≤x≤1... 2018-01-09 设随机变量X-N(0 1)求Y=e^x概率密度? 2015-04-30 设二维随机变量(X,Y...