【单选题】【消耗次数：1】
混凝土强度等级是指（）
①
立方体抗压强度平均值
②
立方体抗压强度标准值
③
棱柱体抗压强度平均值
④
棱柱体抗压强度标准值
参考答案：
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相关题目
【单选题】
混凝土立方体抗压强度试件的标准尺寸为（）。
①
100mm×100mm×100mm
②
150mm×150mm×150mm
③
200mm×200mm×200mm
④
70．7mm×70．7mm×70．7mm
【单选题】
确定混凝土强度等级的依据是混凝土立方体抗压强度，其标准试件的尺寸是（）
①
100mm×100mm×100mm
②
150mm×150mm×150mm
③
200mm×200mm×200mm
④
150mm×150mm×300mm
随机题目
【单选题】
已知<imgwidth="202"height="24"v:shapes="_x0000_i1076"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image084.png">,且有<imgwidth="134"height="24"v:shapes="_x0000_i1077"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image086.png">,则（）
①
<imgwidth="138"height="46"v:shapes="_x0000_i1078"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image088.png">
②
<imgwidth="128"height="46"v:shapes="_x0000_i1079"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image090.png">
③
<imgwidth="128"height="46"v:shapes="_x0000_i1080"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image092.png">
④
<imgwidth="150"height="46"v:shapes="_x0000_i1081"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds03.files/image094.png">
【单选题】
若存在一可逆阵<imgwidth="18"height="18"v:shapes="_x0000_i1303"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image388.png">使得<imgwidth="54"height="22"v:shapes="_x0000_i1304"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image390.png">为对角阵，其中<imgwidth="134"height="84"v:shapes="_x0000_i1305"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image392.png">，则<imgwidth="18"height="18"v:shapes="_x0000_i1306"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image388.png">为（）
①
<imgwidth="84"height="84"v:shapes="_x0000_i1307"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image394.png">
②
<imgwidth="84"height="84"v:shapes="_x0000_i1308"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image394.png">
③
<imgwidth="84"height="84"v:shapes="_x0000_i1309"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image396.png">
④
<imgwidth="84"height="84"v:shapes="_x0000_i1310"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image398.png">
【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<imgwidth="12"height="14"v:shapes="_x0000_i1185"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image253.png">个随机变量<imgwidth="86"height="22"v:shapes="_x0000_i1186"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image239.png">是独立同分布，<imgwidth="164"height="42"v:shapes="_x0000_i1187"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image255.png"><imgwidth="32"height="20"v:shapes="_x0000_i1188"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image257.png"><imgwidth="115"height="42"v:shapes="_x0000_i1189"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image259.png">，则下列结论中，正确的是（）
①
<imgwidth="12"height="14"v:shapes="_x0000_i1190"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image261.png">是<imgwidth="12"height="12"v:shapes="_x0000_i1191"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image263.png">的无偏估计量
②
<imgwidth="12"height="14"v:shapes="_x0000_i1192"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image261.png">是<imgwidth="12"height="12"v:shapes="_x0000_i1193"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image263.png">的极大似然估计量
③
<imgwidth="12"height="14"v:shapes="_x0000_i1194"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image261.png">是<imgwidth="12"height="12"v:shapes="_x0000_i1195"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image263.png">的极大似然估计量
④
<imgwidth="12"height="14"v:shapes="_x0000_i1196"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image261.png">是<imgwidth="12"height="12"v:shapes="_x0000_i1197"src="http://wljy.whut.edu.cn:80/uploadfiles/word/xxdsb11.files/image263.png">的极大似然估计量
【单选题】
若<imgwidth="80"height="21"v:shapes="_x0000_i1198"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image288.png">都存在，则下面命题中错误的是（）
①
<imgwidth="247"height="21"v:shapes="_x0000_i1199"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image290.png">
②
<imgwidth="215"height="21"v:shapes="_x0000_i1200"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image292.png">
③
<imgwidth="152"height="21"v:shapes="_x0000_i1201"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image294.png">
④
<imgwidth="163"height="21"v:shapes="_x0000_i1202"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb09.files/image296.png">
【单选题】
设A，B表任意二随机事件，则下面错误的是（）
①
<imgwidth="16"height="17"v:shapes="_x0000_i1102"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image152.png">与<imgwidth="16"height="20"v:shapes="_x0000_i1103"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image154.png">互不相容
②
<imgwidth="110"height="21"v:shapes="_x0000_i1104"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image156.png">
③
<imgwidth="27"height="20"v:shapes="_x0000_i1105"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image158.png">表示<imgwidth="16"height="17"v:shapes="_x0000_i1106"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image152.png">与<imgwidth="16"height="17"v:shapes="_x0000_i1107"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image161.png">都不发生
④
若<imgwidth="80"height="21"v:shapes="_x0000_i1108"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image163.png">，则<imgwidth="239"height="25"v:shapes="_x0000_i1109"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb06.files/image165.png">
【单选题】
<imgwidth="44"height="16"v:shapes="_x0000_i1068"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image062.png">矩阵<imgwidth="18"height="18"v:shapes="_x0000_i1069"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image008.png">的秩为<imgwidth="18"height="16"v:shapes="_x0000_i1070"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image065.png">，则（）
①
<imgwidth="18"height="18"v:shapes="_x0000_i1071"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image008.png">的任意一个<imgwidth="18"height="16"v:shapes="_x0000_i1072"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image065.png">阶子式都不等于零
②
<imgwidth="18"height="18"v:shapes="_x0000_i1073"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image008.png">的任意一个<imgwidth="42"height="20"v:shapes="_x0000_i1074"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image068.png">阶子式都不等于零
③
<imgwidth="18"height="18"v:shapes="_x0000_i1075"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image008.png">的任意<imgwidth="18"height="16"v:shapes="_x0000_i1076"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image065.png">个列向量必线性无关
④
对于任一<imgwidth="18"height="16"v:shapes="_x0000_i1077"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image065.png">维列向量<imgwidth="14"height="20"v:shapes="_x0000_i1078"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image070.png">，矩阵<imgwidth="56"height="28"v:shapes="_x0000_i1079"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image072.png">的秩都为<imgwidth="18"height="16"v:shapes="_x0000_i1080"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image065.png">
【单选题】
<imgwidth="183"height="25"v:shapes="_x0000_i1194"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image285.png">，且<imgwidth="21"height="25"v:shapes="_x0000_i1195"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image287.png">与<imgwidth="22"height="25"v:shapes="_x0000_i1196"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image289.png">相互独立，则<imgwidth="68"height="25"v:shapes="_x0000_i1197"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image291.png">（）
①
<imgwidth="84"height="25"v:shapes="_x0000_i1198"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image293.png">
②
<imgwidth="92"height="25"v:shapes="_x0000_i1199"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image295.png">
③
<imgwidth="88"height="41"v:shapes="_x0000_i1200"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image297.png">
④
<imgwidth="96"height="41"v:shapes="_x0000_i1201"src="http://wljy.whut.edu.cn/uploadfiles/word/xxdsb08.files/image299.png">
【单选题】
设<imgwidth="14"height="16"v:shapes="_x0000_i1089"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image004.png">元齐次线性方程组<imgwidth="54"height="20"v:shapes="_x0000_i1090"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image030.png">的通解为<imgwidth="108"height="32"v:shapes="_x0000_i1091"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image083.png">则矩阵<imgwidth="18"height="18"v:shapes="_x0000_i1092"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image008.png">的秩（）
①
<imgwidth="62"height="24"v:shapes="_x0000_i1093"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image086.png">
②
<imgwidth="90"height="24"v:shapes="_x0000_i1094"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image088.png">
③
<imgwidth="66"height="24"v:shapes="_x0000_i1095"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image079.png">
④
<imgwidth="18"height="18"v:shapes="_x0000_i1096"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds04.files/image008.png">的每行元素之和都不等于零
【单选题】
以下结论中不正确的是（）
①
若存在可逆矩阵<imgwidth="18"height="20"v:shapes="_x0000_i1238"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image243.png">，使<imgwidth="70"height="24"v:shapes="_x0000_i1239"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image245.png">，则<imgwidth="18"height="18"v:shapes="_x0000_i1240"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image246.png">是正定矩阵
②
二次型<imgwidth="158"height="28"v:shapes="_x0000_i1241"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image248.png">是正定二次型
③
<imgwidth="14"height="16"v:shapes="_x0000_i1242"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image249.png">元实二次型正定的充分必要条件是<imgwidth="18"height="24"v:shapes="_x0000_i1243"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image233.png">的正惯性指数为<imgwidth="14"height="16"v:shapes="_x0000_i1244"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image249.png">
④
<imgwidth="14"height="16"v:shapes="_x0000_i1245"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image249.png">阶实对称矩阵<imgwidth="18"height="18"v:shapes="_x0000_i1246"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image246.png">正定的充分必要条件是<imgwidth="18"height="18"v:shapes="_x0000_i1247"src="http://wljy.whut.edu.cn/uploadfiles/word/xxds05.files/image246.png">的特征值全为正数