发布时间 : 星期五 文章本科线性代数总复习 - 文档更新完毕开始阅读
第一章行列式 一、单项选择题
1.二阶行列式
k?122k?1≠0的充分必要条件是( )
A.k≠-1 B.k≠3 C.k≠-1且k≠3 D.k≠-1或≠3 答案:C a1b1aab2.设行列式
=1,1c1a=2,则
11?c12b2a2c2a2b )2?c=(2A.-3 B.-1 C.1 D.3
答案:D
?3x1?kx2?x3?03.如果方程组??4x2?x3?0有非零解,则 k=( ) ??4x2?kx3?0A.-2 B.-1 C.1
D.2
答案:B
a11a12a13a115a11?2a12a134.设行列式D=a21a22a23=3,D1=a215a21?2a22a23,则D1的值为( a31a32a33a315a31?2a32a33A.-15 B.-6 C.6 D.15
答案:C
0?115.3阶行列式aij=10?1中元素a21的代数余了式A21=( ) ?110A.-2 B.-1 C.1 D.2
答案:C
a11a12a132a112a122a136.已知a21a22a23=3,那么a21a22a23=( )
a31a32a33?2a31?2a32?2a33A.-24 B.-12 C.-6 D.12
答案:B 二、填空题
1
)
a112a124a226a323a13a11a12a22a32a13a23a337.已知3阶行列式
2a213a316a239a33=6,则
a21a31=_______________.答案:1/6
8.设3阶行列式D3的第2列元素分别为1,-2,3,对应的代数余子式分别为-3,2,1,则
D3=__________________.答案:-4 9.已知行列式a1?b1a1?b1,则
a1b1a2?b2a?______.答案:2
2?b??42a2b2三、计算题
111410.求4阶行列式
1131的值.
1211111100030003解:原式=
11310020
1211?1211111111110003002?0020??3010??601
0100111111111?6120011.计算四阶行列式0120的值.
00122001120200解:原式=012?2120??15 0010121234512.设
77733,求AA?3245231?A32?A33,A34?A35.
3332246523答案:0,0.
一章矩阵
一、单项选择题
1.设A为三阶矩阵,|A|=a≠0,则其伴随矩阵A*的行列式|A*|=( A.a B.a2 C.a3
D.a4
) 2
答案:B
2.设A、B为同阶可逆矩阵,则以下结论正确的是( ) A.|AB|=|BA| C.(AB)-1=A-1B-1
B.|A+B|=|A|+|B| D.(A+B)2=A2+2AB+B2
答案:A
3.设A可逆,则下列说法错误的是( ) ..A.存在B使AB=E C.A相似于对角阵 答案:C
4.设A为3阶方阵,且|A|=2,则|2A-1|=( ) A.-4 B.-1 C.1 答案:D
?15.设矩阵A=(1,2),B=??3
?
2??1?,C=???44??253??,则下列矩阵运算中有意义6??
B.|A|≠0
D.A的n个列向量线性无关
D.4
的是( )
A.ACB B.ABC C.BAC D.CBA 答案:B
6.设A为任意n阶矩阵,下列矩阵中为反对称矩阵的是( ) A.A+AT B.A-AT C.AAT D.ATA 答案:B
?a?7.设2阶矩阵A=?c??dA.???c?b??*?,则A=( ) d?c???d? C.??c?a???b?? ?a????d?b??? B.?b?a???d D.???b??c?? a??答案:A
?3?8.矩阵??1?3??的逆矩阵是( ) 0???0?0?1????1A.? B.?3?3????0?3??1? C.?3???3?1??
??11? D.???1??
1?
?3? 0??
答案:C
9.设A为n阶方阵,λ为实数,则|λA|=( )
3
A.λ|A| B.|λ||A| C.λn|A| D.|λ|n|A| 答案:C
10.设A为n阶方阵,令方阵B=A+AT,则必有( ) A.BT=B B.B=2A C.BT=-B D.B=0 答案:A
11.设A、B为同阶方阵,下列等式中恒正确的是( ) A.AB=B B.?A?B??1?A?1?B?1
C.A?B?A?B D.?A?B?T?AT?BT
答案:D
12.设A为四阶矩阵,且A?2,则A*?( ) A.2 B.4 C.8 D.12
答案:C
13.设A,B为同阶可逆方阵,则下列等式中错误..
的是( ) A.|AB|=|A| |B| B. (AB)-1=B-1A-1 C. (A+B)-1=A-1+B-1 D. (AB)T=BTAT答案:C
14.设A为三阶矩阵,且|A|=2,则|(A*)-1|=( ) A.
14 B.1 C.2 D.4
答案:A
15.设A为3阶方阵,且?13A?13,则|A|?( )
A.-9 B.-3 C.-1 D.9
答案:B
16.设A、B为n阶方阵,满足A2=B2,则必有( ) A.A=B B.A= -B C.|A|=|B| D.|A|2
=|B|2
答案:D
17.设A为5×4矩阵,若秩(A)=4,则秩(5AT
)为( ) A.2 B.3 C.4 D.5 答案:C
18.设A,B,C为同阶方阵,下面矩阵的运算中不成立...的是( ) A.(A+B)T=AT+BT
B.|AB|=|A||B|
C.A(B+C)=BA+CA D.(AB)T
=BT
AT
答案:C
19.若矩阵A可逆,则下列等式成立的是( ) A.A=
1A* B.A?0 C.(A2)?1?(A?1)2 D.(3A)?1?3A?1A
答案:C
20.设A为2阶矩阵,若3A=3,则2A?( )
4