2022年10月概率论与数理统计(经管类)试题)
卷面总分:100分
试卷年份:2022.10
是否有答案:有
作答时间: 150分钟
设X,Y 为任意随机变量,则下列各式一定成立的是
- A、E(XY)=E(X)E(Y)
- B、D(XY)=D(X)D(Y)
- C、D(X-)=D(X)-D(Y)
- D、D(X-Y)=D(Y-X)
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Stack trace:
#0 /data/zikao/sites/www.fjzikao.net/www/phpcms/model/get_model.class.php(59): db_mysqli->fetch_next()
#1 /data/zikao/sites/www.fjzikao.net/www/caches/caches_template/default/content/yzb_exam_detail.php(142): get_model->fetch_next()
#2 /data/zikao/sites/www.fjzikao.net/www/phpcms/modules/yzb/exam.php(293): include('/data/zikao/sit...')
#3 /data/zikao/sites/www.fjzikao.net/www/phpcms/libs/classes/application.class.php(61): exam->detail()
#4 /data/zikao/sites/www.fjzikao.net/www/phpcms/libs/classes/application.class.php(37): application->init()
#5 /data/zikao/sites/www.fjzikao.net/www/phpcms/base.php(251): application->__construct()
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