【单选题】【消耗次数：1】
设随机变量X的方差<imgwidth="144"height="25"v:shapes="_x0000_i1025"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image002.png">，则X的数学期望<imgwidth="54"height="21"v:shapes="_x0000_i1026"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image004.png">（）
①
16
②
20
③
4
④
<imgwidth="33"height="25"v:shapes="_x0000_i1027"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image006.png">
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【单选题】
设随机变量<imgwidth="19"height="17"v:shapes="_x0000_i1256"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image266.png">的均值<imgwidth="68"height="21"v:shapes="_x0000_i1257"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image360.png">，方差<imgwidth="75"height="25"v:shapes="_x0000_i1258"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image362.png">，则<imgwidth="60"height="25"v:shapes="_x0000_i1259"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image364.png">（）
①
<imgwidth="54"height="25"v:shapes="_x0000_i1260"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image366.png">
②
<imgwidth="54"height="25"v:shapes="_x0000_i1261"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image368.png">
③
<imgwidth="41"height="18"v:shapes="_x0000_i1262"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image370.png">
④
<imgwidth="41"height="18"v:shapes="_x0000_i1263"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image372.png">
【单选题】
设随机变量<imgwidth="100"height="25"v:shapes="_x0000_i1119"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image157.png">独立同分布，且<imgwidth="223"height="41"v:shapes="_x0000_i1120"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image159.png">，则<imgwidth="115"height="46"v:shapes="_x0000_i1121"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image161.png">（）
①
<imgwidth="37"height="21"v:shapes="_x0000_i1122"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image163.png">
②
<imgwidth="36"height="21"v:shapes="_x0000_i1123"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image165.png">
③
<imgwidth="16"height="41"v:shapes="_x0000_i1124"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image130.png">
④
1
【单选题】
设随机变量<imgwidth="19"height="17"v:shapes="_x0000_i1242"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image266.png">的分布函数为<imgwidth="132"height="75"v:shapes="_x0000_i1243"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image335.png">，则<imgwidth="48"height="21"v:shapes="_x0000_i1244"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image337.png">（）
①
<imgwidth="57"height="35"v:shapes="_x0000_i1245"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image339.png">
②
<imgwidth="55"height="35"v:shapes="_x0000_i1246"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image341.png">
③
<imgwidth="108"height="35"v:shapes="_x0000_i1247"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image343.png">
④
<imgwidth="64"height="34"v:shapes="_x0000_i1248"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image345.png">
【单选题】
设二维随机变量<imgwidth="46"height="21"v:shapes="_x0000_i1049"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image042.png"><imgwidth="79"height="41"v:shapes="_x0000_i1050"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image044.png">，则<imgwidth="84"height="21"v:shapes="_x0000_i1051"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image046.png">（）
①
<imgwidth="16"height="41"v:shapes="_x0000_i1052"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image048.png">
②
3
③
18
④
36
【单选题】
<imgwidth="13"height="21"v:shapes="_x0000_i1174"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image254.png">与<imgwidth="13"height="17"v:shapes="_x0000_i1175"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image256.png">的相关系数<imgwidth="50"height="26"v:shapes="_x0000_i1176"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image258.png">，表示<imgwidth="13"height="21"v:shapes="_x0000_i1177"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image254.png">与<imgwidth="13"height="17"v:shapes="_x0000_i1178"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image256.png">（）
①
相互独立
②
不线性相关
③
存在常数<imgwidth="27"height="21"v:shapes="_x0000_i1179"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image260.png">使<imgwidth="116"height="27"v:shapes="_x0000_i1180"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image262.png">
④
满足<imgwidth="164"height="29"v:shapes="_x0000_i1181"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image264.png">
【单选题】
设随机变量<imgwidth="19"height="17"v:shapes="_x0000_i1111"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image123.png">的数学期望<imgwidth="68"height="21"v:shapes="_x0000_i1112"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image145.png">，方差<imgwidth="75"height="25"v:shapes="_x0000_i1113"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image147.png">，则由切比雪夫不等式有<imgwidth="118"height="21"v:shapes="_x0000_i1114"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image149.png">（）
①
<imgwidth="16"height="41"v:shapes="_x0000_i1115"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image151.png">
②
<imgwidth="16"height="41"v:shapes="_x0000_i1116"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image153.png">
③
<imgwidth="16"height="41"v:shapes="_x0000_i1117"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image130.png">
④
<imgwidth="15"height="41"v:shapes="_x0000_i1118"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image132.png">
【单选题】
设连续型随机变量<imgwidth="19"height="17"v:shapes="_x0000_i1182"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image266.png">的密度函数为<imgwidth="36"height="21"v:shapes="_x0000_i1183"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image268.png">，则当（）时，<imgwidth="80"height="35"v:shapes="_x0000_i1184"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image270.png">为随机变量<imgwidth="19"height="17"v:shapes="_x0000_i1185"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image266.png">数学期望.
①
<imgwidth="80"height="35"v:shapes="_x0000_i1186"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image270.png">收敛
②
<imgwidth="36"height="21"v:shapes="_x0000_i1187"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image268.png">为有界函数
③
<imgwidth="88"height="29"v:shapes="_x0000_i1188"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image274.png">
④
<imgwidth="80"height="35"v:shapes="_x0000_i1189"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image270.png">绝对收敛
【单选题】
设随机变量X的期望<imgwidth="41"height="21"v:shapes="_x0000_i1042"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image028.png">和方差<imgwidth="42"height="21"v:shapes="_x0000_i1043"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image030.png">都存在，则对任意正数<imgwidth="13"height="15"v:shapes="_x0000_i1044"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image032.png">，有（）
①
<imgwidth="180"height="41"v:shapes="_x0000_i1045"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image034.png">
②
<imgwidth="180"height="41"v:shapes="_x0000_i1046"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image036.png">
③
<imgwidth="180"height="41"v:shapes="_x0000_i1047"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image038.png">
④
<imgwidth="180"height="41"v:shapes="_x0000_i1048"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image040.png">
【单选题】
设随机变量X和Y相互独立，且都服从<imgwidth="61"height="25"v:shapes="_x0000_i1053"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image050.png">，若<imgwidth="172"height="21"v:shapes="_x0000_i1054"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image052.png">，其中<imgwidth="27"height="21"v:shapes="_x0000_i1055"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image054.png">为常数，则<imgwidth="28"height="25"v:shapes="_x0000_i1056"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image056.png">=（）
①
<imgwidth="51"height="44"v:shapes="_x0000_i1057"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image058.png">
②
<imgwidth="51"height="44"v:shapes="_x0000_i1058"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image060.png">
③
<imgwidth="51"height="41"v:shapes="_x0000_i1059"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image062.png">
④
<imgwidth="50"height="41"v:shapes="_x0000_i1060"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image064.png">
【单选题】
设<imgwidth="77"height="21"v:shapes="_x0000_i1232"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image322.png">，<imgwidth="73"height="17"v:shapes="_x0000_i1233"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image324.png">，则<imgwidth="15"height="17"v:shapes="_x0000_i1234"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image280.png">服从于（）分布
①
<imgwidth="48"height="21"v:shapes="_x0000_i1235"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image327.png">
②
<imgwidth="48"height="21"v:shapes="_x0000_i1236"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image327.png">
③
<imgwidth="46"height="21"v:shapes="_x0000_i1237"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image329.png">
④
<imgwidth="48"height="21"v:shapes="_x0000_i1238"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image331.png">
随机题目
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Direction: Fill in the blanks with the phrases given below. Change the form if necessary.[have access to; go off; desperate for; put up with; always the case; give advice; concentrate on; arrive at; make an effort; come in handy]2. Dont throw those old textbooks away. They may[填空1]some day.
【简答题】
Direction: Fill in the blanks with the words given below. Change the form if necessary.[assumption; contact; cliff; equivalent; emergency; outweigh; height; rummage; vibration; bugbear]7. He deals with[填空1]promptly.
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八国联军侵华战争时签订了[填空]条约。
【简答题】
中国近代史的起点是[填空]。
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谈谈你对自然垄断的看法。
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简述边际报酬递减规律的内容
【简答题】
试述替代效应和收入效应的概念。