单选
设随机变量X~B(4,0.5),Y服从区间[2,6]上的均匀分布,则E(2X—Y)=()。
A 0 B 2 C -2 D 4
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单选
设X、Y为随机变量,D(X)=4,D(Y)=16,Cov(X,Y)=2,ρXY=()。
A <img src="https://www.beizhujiaoyu.com/uploads/202208/164696753423221.png" width="16" height="34" />  B <img src="https://www.beizhujiaoyu.com/uploads/202208/164696753918381.png" width="16" height="34" />  C <img src="https://www.beizhujiaoyu.com/uploads/202208/164696754380491.png" width="15" height="33" />  D <img src="https://www.beizhujiaoyu.com/uploads/202208/164696754778961.png" width="15" height="34" /> 
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单选
设随机变量X的E(X)=2,D(X)=3,用切比雪夫不等式估计P{|X—E(X)|≤3}≥ ()。
A <img src="https://www.beizhujiaoyu.com/uploads/202208/164696899974471.png" width="15" height="34" />  B <img src="https://www.beizhujiaoyu.com/uploads/202208/164696900340461.png" width="16" height="34" />  C <img src="https://www.beizhujiaoyu.com/uploads/202208/164696900891461.png" width="16" height="34" />  D 2
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单选
A 均匀 B 泊松 C 指数 D 二项
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单选
A <img src="https://www.beizhujiaoyu.com/uploads/202208/164696757766701.png" width="34" height="34" />  B 0 C <img src="https://www.beizhujiaoyu.com/uploads/202208/164696758051901.png" width="16" height="34" />  D 无法计算
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单选
()。
A <img src="https://www.beizhujiaoyu.com/uploads/202208/164696700674351.png" width="17" height="34" />  B <img src="https://www.beizhujiaoyu.com/uploads/202208/164696701086791.png" width="16" height="34" />  C <img src="https://www.beizhujiaoyu.com/uploads/202208/164696701431021.png" width="14" height="34" />  D <img src="https://www.beizhujiaoyu.com/uploads/202208/164696701949111.png" width="15" height="33" /> 
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单选
设随机变量X服从参数λ=2的泊松分布,F(x)为X的分布函数,则下列正确的是()。
A P(X≤1)=2e-2 B F(1)=e-2 C F(0)=e-2 D P(X=0)=P(X=1)
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单选
袋中装有7个白球和8个黑球,一次取出4个球后,发现是同一种颜色的,这种颜色是黑色的概率为()。
A <img src="https://www.beizhujiaoyu.com/uploads/202208/164696894177451.png" width="15" height="33" />  B <img src="https://www.beizhujiaoyu.com/uploads/202208/164696894572691.png" width="15" height="33" />  C <img src="https://www.beizhujiaoyu.com/uploads/202208/164696895024591.png" width="15" height="34" />  D <img src="https://www.beizhujiaoyu.com/uploads/202208/164696895659491.png" width="16" height="34" /> 
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单选
A <img src="https://www.beizhujiaoyu.com/uploads/202208/1646976596461.png" width="16" height="34" /> B <img src="https://www.beizhujiaoyu.com/uploads/202208/164697660049761.png" width="16" height="34" /> C 1 D <img src="https://www.beizhujiaoyu.com/uploads/202208/164697660650141.png" width="16" height="34" />
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()。
A <img src="https://www.beizhujiaoyu.com/uploads/202208/164697473279741.png" width="15" height="34" /> B 1 C 2 D <img src="https://www.beizhujiaoyu.com/uploads/202208/164697473724631.png" width="16" height="34" />
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