设 (I) 计算行列式 A ; (II) 当实数a为何值时,方程组有无穷多解,并求其通解
暂无解析
对前来寻求帮助的人,社会工作者首先需要做的工作是()。
Postage______,thenecklacewillcostyouatleast650yuan.
________evidencethatlanguageacquiringabilitymustbestimulated.
设A是2阶矩阵,且
ProfessorWang,_______forhisinformativelectures,waswarmlyreceivedbyhisstudents.