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From: "ma" <ma@cugb.edu.cn>
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ṩһ˼·
ԼF^TFת,F^-1F
֤ABǿɽ
AAԷֽA=C*C^T
BBԷֽBD*D^T
AB=BAд
C*C^T*D*D^T=D*D^T*C*C^T          ʽ1
ȻͬʱC^-1,ͬʱҳC^-1^T,Ե
C^T*D*D^T*C^T^-1=C^-1*D*D^T*C    ʽ2
ʱԿʽ2ߵľ˵ʽD*D^TΪBBʽ2ߵľ
õľֵȫΪʵʽ2ʽ1ͬ任ģںͬ任?
Ĺָʽ1˵ĽֵҲȫΪʵAB
: ABΪABBA֤AB
: ֤3x

