已知行列式D= https://assets.asklib.com/psource/2015110316140880817.png ,则A11+A21+A31+A41=()。
已知|a|=1,|b|= https://assets.asklib.com/psource/201510271129078549.jpg ,且 https://assets.asklib.com/psource/201510271129117813.jpg =π/4,则|a+b|等于:()
已知a是大于零的常数, https://assets.asklib.com/psource/2015102916130870715.jpg ,则f'(0)的值应是()。
已知|a|=2,|b|= https://assets.asklib.com/psource/2015102711295155630.jpg ,且a?b=3,则|a×b|等于()
已知二次型 https://assets.asklib.com/psource/2015102914333823758.jpg 的秩等于2,则系数a等于().
已知矩阵A= https://assets.asklib.com/psource/2015110316094670550.png ,则A的秩r(A)一()
如图所示,已知主、俯视图,正确的A向视图是图()。https://assets.asklib.com/psource/2014121210183792640.png
(2011)设3阶矩阵A= https://assets.asklib.com/psource/2015110316062911517.png ,已知A的伴随矩阵的秩为1,则a=()
设已知点A(1,0, https://assets.asklib.com/psource/2016071509392644583.jpg )和B(4,2 https://assets.asklib.com/psource/2016071509392644583.jpg , https://assets.asklib.com/psource/201607150939294784.jpg ),则方向和一致的单位向量是()。
已知 https://assets.asklib.com/psource/2016030217175115322.jpg ,证明不等式: https://assets.asklib.com/psource/2016030217175344575.jpg ,当且仅当a=b=c时取等号。
已知集合 https://assets.asklib.com/psource/2016030215455764973.jpg ,若A∩B=B,求实数m的值。
已知:i=100•sin( https://assets.asklib.com/psource/2016051617103834071.jpg t+150°)A,t=0时,i等于()A。
已知:i=100•sin( https://assets.asklib.com/psource/2016051211253095947.jpg t+30°)A,t=0时,i等于()A。
已知图示结构EI=常数,A、B两点的相对水平线位移为:() https://assets.asklib.com/psource/2016071811133019563.jpg https://assets.asklib.com/psource/2016071811132856683.jpg
已知数列{a n }中,a 1 =1,且 https://assets.asklib.com/psource/2016030616111544372.jpg (1)求证:数列 https://assets.asklib.com/psource/2016030616111743839.jpg 是等差数列; (2)求数列{a n }的通项公式。
已知 https://assets.asklib.com/psource/2015102711245533143.jpg ,则a的值是:()
设3阶方阵 https://assets.asklib.com/psource/2015102914275196289.jpg ,已知A是奇异阵,则R(A)等于().
图10-40所示正弦交流电路,已知=1∠0°A,则图中为()A。https://assets.asklib.com/psource/2015110113485264774.jpg
已知直线AB的方位角a ab =87°, https://assets.asklib.com/psource/2015102809083881644.jpg =∠ABC=290°,则直线BC的方位角a https://assets.asklib.com/psource/2015102809084379277.jpg 为()
已知 https://assets.asklib.com/psource/2015102817280557555.jpg [(x-a)/(x+a)]= https://assets.asklib.com/psource/2015102817280682073.jpg e -x dx,则a的值为()
点沿轨迹已知的平面曲线运动时,其速度大小不变,加速度a应为:() https://assets.asklib.com/psource/2016071916544916633.jpg https://assets.asklib.com/psource/2016071916544682426.jpg
已知主、俯视图,如图A-10所示,左视图正确的是()图。https://assets.asklib.com/psource/2015042309223239906.jpg
已知A={x|x>-1},那么正确的是()。https://assets.asklib.com/psource/2016030118013359124.jpg
绘图题:已知图-21(a)主、俯两视图,画出左视图。https://assets.asklib.com/psource/2015052411285056925.jpg