西南大学《线性代数》（英文版）课件-第10部分.pdfVIP免费

�g.§4.5�g.9ÙÝ�L«ÜHŒÆêƆÚOÆ��g.�g.�g.�½Â½Â¡ê•P¥�'un‡Cþx1,···,xn��gàgõ‘ªa11x21+2a12x1x2+2a12x1x3+···+2a1nx1xn+a22x22+2a23x2x3+···+2a2nx2xn+······+annx2n•ê•Pþ�˜‡n��g.,{¡�g..P•f(x1,···,xn)½f.�g.�g.�g.�Ý�d�g.�½ÂŒ•,�i≤jž,aijâk½Â.e‰½�g.f,�i>jž,Paij=aji.u´f(x1,···,xn)=a11x21+a12x1x2+···+a1nx1xn+a21x2x1+a22x22+···+a2nx2xn+······+an1xnx1+an2xnx2+···+annx2n=n�i,j=1aijxixj.,˜•¡,|^Ý��¦{•Œ±•B/L«�g..f(x1,···,xn)=x1(a11x1+a12x2+···+a1nxn)+x2(a21x1+a22x2+···+a2nxn)+······+xn(an1x1+an2x2+···+annxn)�g.�g.�g.�Ý�=(x1,x2,···,xn)...