根据式子求a表示什么数?1.a＜-a2./a/=a3./a/=-a4./a/＞a
根据式子求a表示什么数?1.a＜-a2./a/=a3./a/=-a4./a/＞a
已知-l＜a＜0，|x-a|=a2．则x的取值范围是（ ）
已知-l＜a＜0，|x-a|=a2．则x的取值范围是（ ）
We have received 1.your letter of 2nd March, with a2. price-list of your products 3.enclosed therein.
We have received 1.your letter of 2nd March, with a2. price-list of your products 3.enclosed therein.
设n阶行列式D中有一行元素及其余子式均为a(a≠0)，k是自然数，则 A: n＝2k，D＝0． B: n＝2k＋1，D＝0． C: n＝2k，D＝a2． D: n＝2k＋1，D＝－a2．
设n阶行列式D中有一行元素及其余子式均为a(a≠0)，k是自然数，则 A: n＝2k，D＝0． B: n＝2k＋1，D＝0． C: n＝2k，D＝a2． D: n＝2k＋1，D＝－a2．
A2.下列哪项不是肝静脉阻塞综合征的临床表现?( ) A: 黄疸 B: 腹水 C: 肝大 D: 溶血
A2.下列哪项不是肝静脉阻塞综合征的临床表现?( ) A: 黄疸 B: 腹水 C: 肝大 D: 溶血
定义运算a*b=a(1-b),下面给出了几个结论：1.a*b=b*a2.若a+b=0,则(a*a)+(b*b)=2ab3.若a*b=0,则a=0...
定义运算a*b=a(1-b),下面给出了几个结论：1.a*b=b*a2.若a+b=0,则(a*a)+(b*b)=2ab3.若a*b=0,则a=0...
如图所示．在光滑水平面上有物体A、B，质量分别为m1、m2．在拉力F作用下，A和B以加速度a做匀加速直线运动．某时刻突然撤去拉力F，此瞬时A和B的加速度为a1、a2．则（ ）
如图所示．在光滑水平面上有物体A、B，质量分别为m1、m2．在拉力F作用下，A和B以加速度a做匀加速直线运动．某时刻突然撤去拉力F，此瞬时A和B的加速度为a1、a2．则（ ）
______ is sea area A2. A: An area within coverage of INMARSAT geostationary satellites B: An area, excluding sea area A1, within coverage of Medium Frequency (MF) coastal radio stations in which continuous DSC alerting is available C: An area within coverage of VHF coast radio stations in which continuous DSC alerting is available D: The extreme polar regions
______ is sea area A2. A: An area within coverage of INMARSAT geostationary satellites B: An area, excluding sea area A1, within coverage of Medium Frequency (MF) coastal radio stations in which continuous DSC alerting is available C: An area within coverage of VHF coast radio stations in which continuous DSC alerting is available D: The extreme polar regions
Page 93-95 Part 6 Paragraph A2. What main idea is the writer implying? A: S. presidents all enjoy being in the public eye. B: The successors of President Kennedy have tried to imitate him. C: Presidents have placed increasing importance on making public appearances. D: Presidents spend too much time making public appearances.
Page 93-95 Part 6 Paragraph A2. What main idea is the writer implying? A: S. presidents all enjoy being in the public eye. B: The successors of President Kennedy have tried to imitate him. C: Presidents have placed increasing importance on making public appearances. D: Presidents spend too much time making public appearances.
设A=(a1，a2，a3，a4)是4阶矩阵，A*为A的伴随矩阵．若(1，0，1，0)T是方程组Ax=0的一个基础解系，则A·x=0的基础解系可为（）。 A: a1，a3． B: a1，a2． C: a1，a2，a3． D: a2，a3，a4．
设A=(a1，a2，a3，a4)是4阶矩阵，A*为A的伴随矩阵．若(1，0，1，0)T是方程组Ax=0的一个基础解系，则A·x=0的基础解系可为（）。 A: a1，a3． B: a1，a2． C: a1，a2，a3． D: a2，a3，a4．