1.设a+b+c=0,求(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)的值2.设a,b,c满足1/a+1/b+1/c=1/(a+b+c),求证:1/(a^2n-1)+1/(b^2n-1)+1/(c^2n-1)=1/[(a^2n-1)+(b^2n-1)+(c^2n-1)]

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1.设a+b+c=0,求(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)的值2.设a,b,c满足1/a+1/b+1/c=1/(a+b+c),求证:1/(a^2n-1)+1/(b^2n-1)+1/(c^2n-1)=1/[(a^2n-1)+(b^2n-1)+(c^2n-1)]

1.设a+b+c=0,求(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)的值2.设a,b,c满足1/a+1/b+1/c=1/(a+b+c),求证:1/(a^2n-1)+1/(b^2n-1)+1/(c^2n-1)=1/[(a^2n-1)+(b^2n-1)+(c^2n-1)]
1.设a+b+c=0,求(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)的值
2.设a,b,c满足1/a+1/b+1/c=1/(a+b+c),求证:1/(a^2n-1)+1/(b^2n-1)+1/(c^2n-1)=1/[(a^2n-1)+(b^2n-1)+(c^2n-1)]

1.设a+b+c=0,求(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)的值2.设a,b,c满足1/a+1/b+1/c=1/(a+b+c),求证:1/(a^2n-1)+1/(b^2n-1)+1/(c^2n-1)=1/[(a^2n-1)+(b^2n-1)+(c^2n-1)]
1.(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)=3/2+ac+bc+ab
因为a+b+c=0,所以(a+b+c)^2=a^2+b^2+c^2+2(ab+bc+ac)=0,所以ab+bc+ac=0
所以有(a^2/2a^2+bc)+(b^2/2b^2+ac)+(c^2/2c^2+ab)=3/2+0=3/2
2.令A=a^2n-1,B=b^2n-1,C=c^2n-1
根据题意有
1/A+1/B+1/C=1/(A+B+C)=1/[(a^2n-1)+(b^2n-1)+(c^2n-1)]

1。把题转化为a+b+c=0的形式就可以了。