轾1犏犏5 故P2=犏犏2犏-犏臌525,P2TBP2=15骣00÷?? . ?÷÷?05桫TTTT 所以P1AP1=P2BP2,P2P1AP1P2=B
轾2犏犏5所以 Q=P1P2T=犏犏1犏犏臌5152-5轾1犏犏5犏犏2犏犏臌5-2轾43犏-犏555. =犏14犏3--犏犏55臌521.(1)由于P=(α,Aα),α10,且lα1Aα 则α与Aα不成比例,且α10,故P可逆. (2)AP=A(α,Aα)=(Aα,Aα)=(Aα,-Aα+6α)
2轾06 即AP=P犏
犏1-1臌 故P-1AP=犏轾06
犏1-1臌轾06 所以A:犏=B
犏1-1臌 B-lE=-l16-1-l=(l+3)(l-2)
故l1=2,l2=-3,故B可以有两个不同的特征值,可以相似对角化,因此A
可以相似对角化.
22.
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23.
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2024年全国硕士研究生招生考试(数学一)--答案解析
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