若随机变量X的方差D(X)存在，a为常数，则[img=249x67]1802f2c16f96412.png[/img]
A: D(X)
B: 1
C: [img=58x66]1802f2c17877038.png[/img]
D: a 2D(X)
A: D(X)
B: 1
C: [img=58x66]1802f2c17877038.png[/img]
D: a 2D(X)
举一反三
- 若随机变量X的方差D(X)存在，a为常数，则[img=249x67]1802f2c2b6e46d0.png[/img] A: D(X) B: 1 C: [img=58x66]1802f2c2bf3c80f.png[/img] D: a 2D(X)
- 若随机变量X的方差D(X)存在，a为常数，则[img=249x67]18031e9705442a0.png[/img] A: D(X) B: 1 C: [img=58x66]18031e970dc4937.png[/img] D: a 2D(X)
- 若随机变量X的方差D(X)存在，a为常数，则[img=249x67]1803c07cf914aaa.png[/img] A: D(X) B: 1 C: [img=58x66]1803c07d00c9eff.png[/img] D: a 2D(X)
- 若随机变量X的方差D(X)存在，a为常数，则[img=249x67]17de6027232ca89.png[/img] 未知类型：{'options': ['D(X)', '1', '', 'a 2D(X)'], 'type': 102}
- 设随机变量X服从均值为2的指数分布，X的分布函数为F(x)，数学期望为E(X)，方差为D(X)，则以下结果正确的是 A: [img=128x28]1802d3b369ab5fe.png[/img] B: D(X)=4 C: P(X<2︱X>1)=F(1) D: P(X>2︱X>1)= F(1) E: [img=112x27]1802d3b372fb534.png[/img] F: D(X)=E(X) G: P(X≤2︱X>1)= F(2) H: [img=82x27]1802d3b37bbbf05.png[/img]