abc不等于0,a+b+c=0,a2/bc+b2/ca+c2/ab=?

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abc不等于0,a+b+c=0,a2/bc+b2/ca+c2/ab=?abc不等于0,a+b+c=0,a2/bc+b2/ca+c2/ab=?abc不等于0,a+b+c=0,a2/bc+b2/ca+c2

abc不等于0,a+b+c=0,a2/bc+b2/ca+c2/ab=?
abc不等于0,a+b+c=0,a2/bc+b2/ca+c2/ab=?

abc不等于0,a+b+c=0,a2/bc+b2/ca+c2/ab=?
∵a^3+b^3+c^3-3abc=(a+b+c)(a^2+b^2+c^2-ab-ac-bc)=0 ∴a^3+b^3+c^3=3abc ∴a2/bc+b2/ca+c2/ab=(a^3+b^3+c^3)/(abc)
=3abc/abc=3

令a^2/(bc)+b^/(ca)+c^2/(ab)=k,则:a^3+b^3+c^3=kabc,
∴a^3+b^3+c^3-3abc=kabc-3abc,
∴(a+b+c)(a^2+b^2+c^2-ab-ca-bc)=kabc-3abc,
而a+b+c=0,∴kabc-3abc=0,∴k=3,即:a^2/(bc)+b^/(ca)+c^2/(ab)=3。

a2/bc+b2/ca+c2/ab=(a^3+b^3+c^3)/(abc)
=(a^3+b^3-(a+b)^3)/(abc)=-(a+b)*ab/(abc)=abc/abc=1