abc都在分母上,那么abc≠0
a+b+c=0 得c=-(a+b)
a^2/bc+b^2/ac+c^2/ab
=(a^3+b^3+c^3)/(abc)
=-[a^3+b^3-(a+b)^3)/[ab(a+b)]
=-[a^3+b^3-a^3-3a^2b-3ab^2-b^3]/[ab(a+b)]
=[3ab(a+b)]/[ab(a+b)]
=3
abc都在分母上,那么abc≠0
a+b+c=0 得c=-(a+b)
a^2/bc+b^2/ac+c^2/ab
=(a^3+b^3+c^3)/(abc)
=-[a^3+b^3-(a+b)^3)/[ab(a+b)]
=-[a^3+b^3-a^3-3a^2b-3ab^2-b^3]/[ab(a+b)]
=[3ab(a+b)]/[ab(a+b)]
=3