【判断题】【消耗次数：1】
数乘对称矩阵及同阶对称矩阵之和仍为对称矩阵。
①
正确
②
错误
参考答案：
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相关题目
【多选题】
设A为n阶对称矩阵，B为n阶反对称矩阵，则下列是对称矩阵的是
①
<img class=jc-formula data-tex={ A }^{ 2 } src=https://huaweicloudobs.ahjxjy.cn/CC624A823BD8B73F0E774F3692397F09.png style=vertical-align: middle;/>
②
<img class=jc-formula data-tex={ B }^{ 2 } src=https://huaweicloudobs.ahjxjy.cn/192A9F0679D608F98C34169BD9A4F824.png style=vertical-align: middle;/>
③
AB-BA
④
AB+BA
【单选题】
设A为n阶实对称矩阵，则（ ）。
①
A的n个特征向量两两相交
②
A的n个特征向量组成单位正交向量组
③
<img src=https://huaweicloudobs.ahjxjy.cn/4AF9B3379B48561D564A85A35D4A6C51.png title=QQ图片20160108180216.png alt=QQ图片20160108180216.png/>
④
<img src=https://huaweicloudobs.ahjxjy.cn/22B4EB3D5B1F0DC92270C0A71B406EAA.png title=QQ图片20160108180224.png alt=QQ图片20160108180224.png/>
【单选题】
设A,B为同阶可逆矩阵，则（ ）
①
AB=BA
②
存在可逆矩阵P，使得<img class=jc-formula data-tex={ P }^{ -1 }AP=B src=https://huaweicloudobs.ahjxjy.cn/B628FBB9DF594DC246E6461761FB0654.png style=vertical-align: middle;/>
③
存在可逆矩阵C，使得<img class=jc-formula data-tex={ C }^{ T }AC=B src=https://huaweicloudobs.ahjxjy.cn/10446E9073E756778585555AA3598B46.png style=vertical-align: middle;/>
④
存在可逆矩阵P，Q,使得PAQ=B
【单选题】
设有一个对称矩阵A，采用压缩存储的方式，将其下三角部分以行序为主序存储到一维数组B中（数组下标从1开始），B数组共有45个元素,则该矩阵是（ ）阶的对称矩阵。
①
A．15
②
B．11
③
C．10
④
D．9
【单选题】
设有一个对称矩阵A，采用压缩存储的方式，将其下三角部分以行序为主序存储到一维数组B中（数组下标从1开始），B数组共有55个元素,则该矩阵是（ ）阶的对称矩阵。 (矩阵中的第1个元素是a1,1 ）
①
A．5
②
B．20
③
C．10
④
D．15
随机题目
【简答题】
如何培养学前儿童记忆的持久性？
【简答题】
简述幼儿记忆发展的特点
【单选题】
学前儿童养成良好的用眼习惯，以下说法正确的是（ ）
①
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②
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③
Normal 0 7.8 磅 0 2 false false false EN-US ZH-CN X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.5pt; mso-bidi-font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:宋体; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-font-kerning:1.0pt;} Normal 0 7.8 磅 0 2 false false false EN-US ZH-CN X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.5pt; mso-bidi-font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:宋体; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-font-kerning:1.0pt;}只要保持正确的看书姿势，长时间的阅读并不会导致儿童眼睛疲劳
④
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【填空题】
最重要并常用的形态指标是（ ）和（ ）。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/><img class="questionIndex" data-index="2" src="/common/images/question_button/BlankSpace2.gif"/>
【填空题】
（ ）规律：上肢最初只有无意识活动，然后学会大把抓，最后才学会用拇指和指拿细小的物体。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/>
【填空题】
（ ）规律：先学会抬头、转头,然后能翻身、学会坐、站立，最后才会走、跑、跳等复杂动作。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/>
【填空题】
幼儿骨的有机物含量较（ ），无机盐含量相对较（ ），所以幼儿骨的弹性大，柔韧性强，而硬度小，容易弯曲变形，不易骨折,一旦骨折，易发生（ ）现象。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/><img class="questionIndex" data-index="2" src="/common/images/question_button/BlankSpace2.gif"/><img class="questionIndex" data-index="3" src="/common/images/question_button/BlankSpace3.gif"/>
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