设随机变量X ~N(20,16),Y ~ N(10,9),且X与Y相互独立,则X+Y服从 分布.
A: [img=72x25]1803da1181e05ce.png[/img]
B: [img=72x25]1803da118a52c9a.png[/img]
C: [img=63x25]1803da1192f9401.png[/img]
D: [img=72x25]1803da119c1e51a.png[/img]
A: [img=72x25]1803da1181e05ce.png[/img]
B: [img=72x25]1803da118a52c9a.png[/img]
C: [img=63x25]1803da1192f9401.png[/img]
D: [img=72x25]1803da119c1e51a.png[/img]
举一反三
- 设随机变量X ~N(20,16),Y ~ N(10,9),且X与Y相互独立,则X+Y服从 分布. A: [img=72x25]18033806a49a26b.png[/img] B: [img=72x25]18033806ae72df3.png[/img] C: [img=63x25]18033806b7d30a7.png[/img] D: [img=72x25]18033806c059242.png[/img]
- 设随机变量X ~N(20,16),Y ~ N(10,9),且X与Y相互独立,则X+Y服从 分布. A: [img=72x25]1803da16459ed17.png[/img] B: [img=72x25]1803da164ddaee2.png[/img] C: [img=63x25]1803da16579d0b0.png[/img] D: [img=72x25]1803da165f948f1.png[/img]
- 设随机变量X ~N(20,16),Y ~ N(10,9),且X与Y相互独立,则X+Y服从 分布.
- 设随机变量X和Y的概率密度分别为:[img=474x78]1802e8d4b06a97d.png[/img]且X和Y相互独立,则2X-3Y的方差为( ). A: 25/16 B: 5/4 C: 25/9 D: 5/3
- 设X~N(0,1),Y~N(1,1)且X,Y相互独立,则P{X+Y[img=14x21]180399638dd0fce.png[/img]1}= .