设A、B为三阶方阵,且行列式*为A的伴随矩阵,则行列式等于()。
A.1
B.-1
C.2
D.-2
参考答案:A
解析:
因为且A、B为三阶方阵,所以行列式
已知圆锥的底面的半径为3cm,高为4cm,则它的侧面积为[ ]
A.15πcm2
B.16πcm2
C.19πcm2
D.24πcm2
We should never forget those who________the success of the revolution. [ ]
A. bled for
B. bleeded for
C. fighting for
D. bled to