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The second question:

A+b+c=0, then a+b=-c, a+c=-b, b+c=-a,

(a+b+c)? =(a+b)? +3(a+b)? c+3(a+b)c? +c?

=a? +3a? b+3ab? +b? +3a? c+6abc+3b? c+3ac? +3bc? +c?

=a? +b? +c? +3a? b+3a? c+3ab? +3b? c+3ac? +3bc? +6abc

=a? +b? +c? +3a? (b+c)+3b? (a+c)+3c? (a+b)+6abc

=a? +b? +c? +3a? (-a)+3b? (-b)+3c? (-c)+6abc

=6abc-2(a? +b? +c? )=0

, so 3abc=a? +b? +c? ;

(a? /2a? +bc)+(b? /2b? +ac)+(c? /2c? +ab)

=(4a? b? c? +2a? b? +2a? c? +a^4bc)/(9a? b? c? +4a? b? +4a? c? +2a^4bc+4b? c? +2ab^4c+2abc^4)

+(4a? b? c? +2a? b? +2b? c? +ab^4c)/(9a? b? c? +4a? b? +4a? c? +2a^4bc+4b? c? +2ab^4c+2abc^4)

+(4a? b? c? +2a? c? +2b? c? +abc^4)/(9a? b? c? +4a? b? +4a? c? +2a^4bc+4b? c? +2ab^4c+2abc^4)

(general fraction, A 4 stands for the fourth power of a)

=( 12a? b? c? +4a? c? +4b? c? +4a? b? +a^4bc+ab^4c+abc^4)/(9a? b? c? +4a? b? +4a? c? +4b? c? +2a^4bc+2ab^4c+2abc^4)

=(9a? b? c? +4a? b? +4a? c? +4b? c? +a^4bc+ab^4c+abc^4+3a? b? c? )/(9a? b? c? +4a? b? +4a? c? +4b? c? +a^4bc+ab^4c+abc^4+a^4bc+ab^4c+abc^4)

Because 3abc=a? +b? +c? , then 3abc*abc=(a? +b? +c? )*abc,

That is, 3a? b? c? =a^4bc+ab^4c+abc^4

So the score is equal up and down, and the original formula (a? /2a? +bc)+(b? /2b? +ac)+(c? /2c? +ab)= 1