在利用戴维宁定理把图A所示电路简化为图B电路时,满足的条件是()。<img src='https://img2.soutiyun.com/shangxueba/ask/2021-09/11/454/20210911114812414.png' />
已知函数<img src='https://img2.soutiyun.com/ask/uploadfile/6546001-6549000/ac4ad9229c5e5f2906a5891b700c37ef.png' />,则函数定义域是()
已知逻辑门电路的输入信号A,B和输出信号Y的波形如下图所示,则该电路实现( )逻辑功能。<img src='https://img2.soutiyun.com/ask/uploadfile/5439001-5442000/20427dd9b6a929dcd0743e6c9f5e6ec9.png' />
A、B、C、D四指标的重要程度逻辑关系如下表所列,已知D的权重值为0.1,则指标A可能的权重值有()。<img src='https://img2.soutiyun.com/shangxueba/ask/3432001-3435000/3433874/ct_cjzcjzm_cjzcjzmchoose_00254(20093).jpg' />
已知两个投资项目A、B的收益率和标准差:<img src='https://img2.soutiyun.com/shangxueba/ask/3921001-3924000/3921292/ct_zychfpesllj_zychfpesllllmchoose_00521(200910).jpg' />下面说法正确的有()。
已知A<img src='https://img2.soutiyun.com/ask/2019-12-05/944436769682424.png' />B且A∈B,下列结论正确的是( ).
f:A→B,g:B→C是两个一对一映射,复合映射<img src='https://img2.soutiyun.com/ask/6114001-6117000/a9eee59481dba95f6b57c645884616c1.jpg' />:A→C满足( ).
设事件A<img src='https://img2.soutiyun.com/latex/latex.action' />B,则下列可能不成立的是( ).
1 设A与B分别表示事件“甲、乙二人射中目标”,则<img src='https://img2.soutiyun.com/ask/6126001-6129000/f7f4bb19667be6e4fe7de67ef934aea3.jpg' />表示事件( ).
已知P(A)=P(B)=<img src='https://img2.soutiyun.com/latex/latex.action' />,则下列结论肯定正确的是( )
下图中,已知R1=R2=R3=1Ω,及R4=2Ω,则a,b两端的等效(总)电阻为()Ω。<img src='https://img2.soutiyun.com/shangxueba/ask/1989001-1992000/1990887/ct_jgzjgysm_jgzjgyschoose_00220(20093).jpg' />
若图a电路中电流表电流为零,则应满足条件______;若图b电路中电流表为零,则应满足条件______。<img src='https://img2.soutiyun.com/ask/2020-02-13/950461275136596.png' />
设A、B为任意两事件,且<img src='https://img2.soutiyun.com/ask/2020-03-06/952348543191874.png' />,P(B)>0,则下列选项必然成立的是( )
已知两个物体A和B的质量以及它们的速率都不相同,若物体A的动量在数值上比物体B的大,则A的动能<img src='https://img2.soutiyun.com/ask/2020-04-29/957026950641931.png' />与B的动能<img src='https://img2.soutiyun.com/ask/2020-04-29/95702696453207.png' />之间()。
从一批产品中随机抽两次,每次抽1件。以A表示事件“两次都抽得正品”,B表示事件“至少抽得一件次品”,则下列关系式中,正确的是()。<img src='https://img2.soutiyun.com/shangxueba/ask/68946001-68949000/68947848/989930489112063.png' />
已知矢量A=ti-2tj+lntk,B=e'i+sintj-3tk,计算积分<img src='https://img2.soutiyun.com/ask/2020-09-23/969723435954376.png' />
有AB两个电脑显示器,已知旧显示器A的宽高比是4:3,新显示器B的宽高比例是16:9,若两个显示器面积相同,问B的宽与A的宽度比是()。<img src='https://img2.soutiyun.com/ask/uploadfile/5463001-5466000/4e11e1787f5551f0337568bad7c7b626.png' />
抗震等级为二级的钢筋混凝土框架结构,其节点核心区的尺寸及配筋如图9—24所示。混凝土强度等级为C40(<img src='https://img2.soutiyun.com/ask/uploadfile/4245001-4248000/9926180a01ab95fa035743d0511ec875.gif' />=19.1N/<img src='https://img2.soutiyun.com/ask/uploadfile/4245001-4248000/2729c75465e61263f64214d281318869.gif' />),主筋、箍筋分别采用HRB400(<img src='https://img2.soutiyun.com/ask/uploadfile/4245001-4248000/e2d9b6735024273397fae06f61b613ef.gif' />=360N/<img src='https://img2.soutiyun.com/ask/uploadfile/4245001-4248000/28e297f3aa89e049d48121e957fd2e48.gif' />)和HPB300(<img src='https://img2.soutiyun.com/ask/uploadfile/4245001-4248000/7f151665f4d5706c9ec61d7910fa7022.gif' />=270N/<img src='https://img2.soutiyun.com/ask/uploadfile/4245001-4248000/d397f9d96db31b48fc11e3e482a004c8.gif' />),箍筋混凝土保护层厚度15mm。已知柱的剪跨比大于2。试问,节点核心区箍筋的配置,为下列何项时,才能最接近又满足规程中的最低构造要求? (A) φ10@150 (B) φ10@100 (C) φ8@100 (D) φ8@75
已知图示斜面的倾角为臼,若要保持物块A静止,则物块与斜面之间的摩擦因数f所应满足的条件为: A.tanf≤θ B.tanf>θ C.tanθ≤f D.tanθ>f<img src='https://img2.soutiyun.com/ask/uploadfile/2685001-2688000/305e7c6a96fffe024f64753b8406f062.jpg' />
若事件A发生必然导致事件B发生,则事件A和B的关系一定是() A.对立事件 B.互不相容事件<img src='https://img2.soutiyun.com/ask/uploadfile/2730001-2733000/951db6a6281c17a69794636791fd4e8d.jpg' /><img src='https://img2.soutiyun.com/ask/uploadfile/2730001-2733000/717e16ee22e504c8784bbe8a3133e12a.jpg' />
已知|a|=2,|b|=<img src='https://img2.soutiyun.com/shangxueba/ask/17682001-17685000/17682935/2015102711295155630.jpg' />,且a?b=3,则|a×b|等于()
已知三阶矩阵A的逆矩阵<img src='https://img2.soutiyun.com/ask/2020-12-02/975754124741759.jpg' />,求矩阵A。
设A,B为随机事件,则<img src='https://img2.soutiyun.com/shangxueba/ask/2022-04/24/213/20220424101858907.png' />=()。
已知图示结构EI=常数,A、B两点的相对水平线位移为:()<img src='https://img2.soutiyun.com/shangxueba/ask/17727001-17730000/17728519/2015102815263390018.jpg' />