- 12
-
矩阵
的特征值是 .
- 14
-
矩阵
的逆矩阵是 .
- 18
-
设实二次型
,则f( )
- A.正定
- B.不定
- C.负定
- D.半正定
- A.<img src="//img1.yqda.net/question-name/22/33a30dc207aed4f3a7c32e912e2e68.png" width="74" height="75"/>
- B.<img src="//img1.yqda.net/question-name/f8/e99d4b4a3152e9a922d839d8d4d2cf.png" width="74" height="75"/>
- C.<img src="//img1.yqda.net/question-name/e3/8c017919c82f45f28b54a686ac48a2.png" width="74" height="75"/>
- D.<img src="//img1.yqda.net/question-name/1c/3f4cb30981f8ccc568574220fce49a.png" width="74" height="75"/>
- A.1
- B.2
- C.3
- D.4
- A.1
- B.2
- C.3
- D.4
- A.0
- B.1
- C.2
- D.3
- A.-2
- B.-1
- C.0
- D.2
- A.若A<sup>2</sup>=0,则A=0
- B.(AB)<sup>2</sup>=A<sup>2</sup>B<sup>2</sup>
- C.若AX=AY,则X=Y
- D.若A+X=B,则X=B-A
- A.(A+B)<sup>T</sup>=A+B
- B.(AB)<sup>T</sup>=-AB
- C.A<sup>2</sup>是对称矩阵
- D.B<sup>2</sup>+A是对称阵
- 26
-
设
,则|AAT|=( )
- A.-49
- B.-7
- C.7
- D.49
- A.-32
- B.-8
- C.8
- D.32