题海让大学四年没有难题
白天模式登陆

题目详情

单选题 设随机变量X的概率密度为则常数a = ( )

A. 3

B.

C. 4

D.

学科：概率论与数理统计

时间：2024-06-19 08:01:17

相关题目

相关作业

题目1
单选题
设<img src="https://tihai-oss-cloud.itihey.com/img/b065f1205a76f74a3d3be62ca3adcb85.png">表示3个事件,则<img src="https://tihai-oss-cloud.itihey.com/img/3c2471fd062539260cfd9cc4b3d4735c.png">表示( )
A. <img src="https://tihai-oss-cloud.itihey.com/img/b065f1205a76f74a3d3be62ca3adcb85.png">中不多于一个发生B. <img src="https://tihai-oss-cloud.itihey.com/img/b065f1205a76f74a3d3be62ca3adcb85.png">中恰有两个发生C. <img src="https://tihai-oss-cloud.itihey.com/img/b065f1205a76f74a3d3be62ca3adcb85.png">都不发生D. <img src="https://tihai-oss-cloud.itihey.com/img/b065f1205a76f74a3d3be62ca3adcb85.png">中有一个发生
题目2
单选题
设 <img src="https://tihai-oss-cloud.itihey.com/img/483a8004bec72b72aaf618a75091f7ef.png">为任意三个事件,则下列说法错误的是()
A. 若事件 <img src="https://tihai-oss-cloud.itihey.com/img/54f4567d5d1aa85ddf2c5f3ce75ecf98.png">与事件 <img src="https://tihai-oss-cloud.itihey.com/img/24f1ca0e68eb0d6682f48a8f0e970a92.png">互斥,则事件 <img src="https://tihai-oss-cloud.itihey.com/img/54f4567d5d1aa85ddf2c5f3ce75ecf98.png">是事件 <img src="https://tihai-oss-cloud.itihey.com/img/24f1ca0e68eb0d6682f48a8f0e970a92.png">的对立事件B. 若事件 <img src="https://tihai-oss-cloud.itihey.com/img/54f4567d5d1aa85ddf2c5f3ce75ecf98.png">是事件 <img src="https://tihai-oss-cloud.itihey.com/img/24f1ca0e68eb0d6682f48a8f0e970a92.png">的对立事件,则事件 <img src="https://tihai-oss-cloud.itihey.com/img/54f4567d5d1aa85ddf2c5f3ce75ecf98.png">与事件 <img src="https://tihai-oss-cloud.itihey.com/img/24f1ca0e68eb0d6682f48a8f0e970a92.png">互斥C. 若 <img src="https://tihai-oss-cloud.itihey.com/img/4de3e190bf60330bf360dcc3f8b282a0.png">且 <img src="https://tihai-oss-cloud.itihey.com/img/96707dc7f644648b15affa990e4857f6.png">,则 <img src="https://tihai-oss-cloud.itihey.com/img/909239dc964c54e4fba97e288405b0b9.png">D. 若 <img src="https://tihai-oss-cloud.itihey.com/img/81de8e6b5dfd279c6c784a4f6a5fcd37.png">,则 <img src="https://tihai-oss-cloud.itihey.com/img/39a9e55530b0dcfee616795ed5ec6980.png">
题目3
单选题
航班起飞延误时间的样本空间可以表示为( )
A. 不确定B. <img src="https://tihai-oss-cloud.itihey.com/img/aea94c13d108a6356a1063e2d71e1863.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/0671a0d22551b3d5eb48f6d9e5de9952.png">D. 以上都不对
题目4
单选题
设A、B为两事件,且<img src="https://tihai-oss-cloud.itihey.com/img/cfb39366f509b40540e527403d4d2538.png">均大于0,则下列公式错误的是( )
A. <img src="https://tihai-oss-cloud.itihey.com/img/a5b79580ba6a42244440a778205dd711.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/b0282de169b412d70794763adc4a0cc2.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/b0e3a3682bbf7faa4ac147d1565460b4.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/5082d482ac952e1ce4c975a52114a1ed.png">
题目5
单选题
有6本中文书和4本外文书,任意往书架摆放,则4本外文书放在一起的概率是( )
A. <img src="https://tihai-oss-cloud.itihey.com/img/7ce9d87170bbc07699ec348b571d5ca0.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/d0169a4b9d991234ee1eb1fca7568004.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/b8b514c9a54ab18394674eb5f091ecd5.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/3f132ba1cdcc78ada705fa3eb4845c41.png">
题目6
单选题
设A、B为两个事件,<img src="https://tihai-oss-cloud.itihey.com/img/dae7d33dd315cc94fd4bc3b68095a061.png">,且<img src="https://tihai-oss-cloud.itihey.com/img/1532f9e65057f780e9add9ccc05a5e94.png">,则下列必成立是( )
A. <img src="https://tihai-oss-cloud.itihey.com/img/33ff2a0135b8e2921d6a5b46aa093d81.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/dede8fa560b30ed7c14f396c02b1f67f.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/d466481188daffdb0f717d3ba8d80d86.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/9e2da7cd0ec5da5414fdd259eff6ea96.png">
题目7
单选题
三人独立破译一个密码,他们能译出的概率分别为<img src="https://tihai-oss-cloud.itihey.com/img/bde37cc6995c57daaf606ecb91874d2d.png">,此密码能被译出的概率是()
A. <img src="https://tihai-oss-cloud.itihey.com/img/8ed26cc723c0b408c5edd8d7eb032ba1.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/bae8fc412b686ee8c87f52da4ca203b5.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/6be55e41a0d1db6a4c5a32f6e60dbce8.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/f09ee5e10b9f2aca45fd99395cac1737.png">
题目8
单选题
设随机变量X的概率密度为<img src="https://tihai-oss-cloud.itihey.com/img/74c86108abdafdc8766ff8faa56b1351.png">则常数a = ( )
A. 3B. <img src="https://tihai-oss-cloud.itihey.com/img/2cddaa83e32a9c17971ec07988a2ac6c.png">C. 4D. <img src="https://tihai-oss-cloud.itihey.com/img/139bf4ef972f36702bfbf5b9b58342be.png">
题目9
单选题
某种商品进行有奖销售,每购买一件有<img src="https://tihai-oss-cloud.itihey.com/img/995955b46d551f311af816723a2e8d5d.png">的中奖率,现某人购买了20件该商品,用随机变量<img src="https://tihai-oss-cloud.itihey.com/img/9470f0a295430c23982f89ddb156c2bc.png">表示中奖的件数,则<img src="https://tihai-oss-cloud.itihey.com/img/9470f0a295430c23982f89ddb156c2bc.png">的分布为 ( )
A. 二项分布B. 正态分布C. 指数分布D. 泊松分布
题目10
单选题
设<img src="https://tihai-oss-cloud.itihey.com/img/44602cae8efb723b24ccea424ff68f8d.png">服从参数为<img src="https://tihai-oss-cloud.itihey.com/img/4dbf44c5360f9968005341375f5a87be.png">的泊松分布,且已知<img src="https://tihai-oss-cloud.itihey.com/img/bcaeb5f78ab49eb3571e4e800d785172.png">,则<img src="https://tihai-oss-cloud.itihey.com/img/08dabc0ee948b81e9922ca3e17e32179.png"> ( )
A. <img src="https://tihai-oss-cloud.itihey.com/img/314bfd6e32f44b36b5a371bbad4d0623.png">B. <img src="https://tihai-oss-cloud.itihey.com/img/f9770f8210f333783eaa52addc6547af.png">C. <img src="https://tihai-oss-cloud.itihey.com/img/2c61d2536f6fc5d472f0aa9471eee738.png">D. <img src="https://tihai-oss-cloud.itihey.com/img/c3be6af53f947ffc2c3c858f479ce0ad.png">
Copyright © 2022 津ICP备2021001502号