【单选题】【消耗次数:1】
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">()
<imgwidth="16"height="41"v:shapes="_x0000_i1052"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image048.png">
3
18
36
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相关题目
【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】 <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_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<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">
【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<imgwidth="35"height="21"v:shapes="_x0000_i1104"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image133.png">是相互独立且均服从正态分布<imgwidth="54"height="41"v:shapes="_x0000_i1105"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image135.png">的随机变量,则<imgwidth="88"height="21"v:shapes="_x0000_i1106"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image137.png">()
①  <imgwidth="29"height="44"v:shapes="_x0000_i1107"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image139.png">
②  <imgwidth="29"height="44"v:shapes="_x0000_i1108"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image139.png">
③  <imgwidth="28"height="46"v:shapes="_x0000_i1109"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image141.png">
④  <imgwidth="29"height="46"v:shapes="_x0000_i1110"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image143.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">
随机题目
【判断题】 超静定结构的内力与材料的性质无关。( )
①  正确
②  错误
【判断题】 超静定次数一般不等于多余约束的个数。( )
①  正确
②  错误
【单选题】 用力法计算图示结构时,不能作为基本结构的是 ( ) 图<img src=https://huaweicloudobs.ahjxjy.cn/9EBEFF84CF4C6A69D587DC594D60AE09.png title=11.png alt=11.png/>
①  <img src=https://huaweicloudobs.ahjxjy.cn/216DE6E37615ADF782AEF69BDEED5839.png title=12.png alt=12.png/>
②  <img src=https://huaweicloudobs.ahjxjy.cn/69F42478B7BD938E33B521537941E9A9.png title=13.png alt=13.png/>
③  <img src=https://huaweicloudobs.ahjxjy.cn/DF760D1243B9830EE8B7F9AB0EFC4025.png title=14.png alt=14.png/>
④  <img src=https://huaweicloudobs.ahjxjy.cn/09DCD550BC1A32FF93325D4FC2A4AF0C.png title=15.png alt=15.png/>
【单选题】 在力法方程的系数和自由项中( )。
①  <img class=jc-formula data-tex={ \delta }_{ ij } src=https://huaweicloudobs.ahjxjy.cn/1A6BA095CB007D4DC9EE3B6FC3B0264B.png style=vertical-align: middle;/>恒大于零
②  <img class=jc-formula data-tex={ \delta }_{ ii } src=https://huaweicloudobs.ahjxjy.cn/EEB3F9F777BFB2E1F56654C501CA4B49.png style=vertical-align: middle;/>恒大于零
③  <img class=jc-formula data-tex={ \delta }_{ ji } src=https://huaweicloudobs.ahjxjy.cn/5FF35BB150CB94FB68514BA3F2D10200.png style=vertical-align: middle;/>恒大于零
④  <img class=jc-formula data-tex={ \Delta }_{ ip } src=https://huaweicloudobs.ahjxjy.cn/0D7CBAB76AAAF393FBFC2BCAB6BF24FB.png style=vertical-align: middle;/>恒大于零
【判断题】 反力互等定理仅对超静定结构才有使用价值。( )
①  正确
②  错误
【判断题】 静定结构由于支座移动引起的位移与刚度无关。( )
①  正确
②  错误
【判断题】 位移互等定理可用于力法中副系数的计算。
①  正确
②  错误
【判断题】 用力法计算超静定结构,选取的基本结构不同,则典型方程中的系数和自由项数值也不同。( )
①  正确
②  错误
【判断题】 同一结构的力法基本体系不是唯一的。( )
①  正确
②  错误
【单选题】 图示结构的超静定次数是( ).<img src=https://huaweicloudobs.ahjxjy.cn/38F2F92BF4A8C8D54A20413F5223E9EF.png title=16.png alt=16.png/>
①  12
②  10
③  8
④  6