关于化简求值与恒等证明1.已知a+b+c=0.求证:(1)a^3+a^2c+b^2c+b^3=abc(2)a^4+b^4+c^4=2a^2b^2+2b^2c^2+2c^2a^22.已知a+b+c=0,求证:a^3+b^3+c^3=3abc3.已知:abc不等于0,ab+bc=2ac求证:(1/a)-(1/b)=(1/b)-(1/c).4.a+b小于0,
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关于化简求值与恒等证明1.已知a+b+c=0.求证:(1)a^3+a^2c+b^2c+b^3=abc(2)a^4+b^4+c^4=2a^2b^2+2b^2c^2+2c^2a^22.已知a+b+c=0,求证:a^3+b^3+c^3=3abc3.已知:abc不等于0,ab+bc=2ac求证:(1/a)-(1/b)=(1/b)-(1/c).4.a+b小于0,
关于化简求值与恒等证明
1.已知a+b+c=0.
求证:(1)a^3+a^2c+b^2c+b^3=abc
(2)a^4+b^4+c^4=2a^2b^2+2b^2c^2+2c^2a^2
2.已知a+b+c=0,求证:a^3+b^3+c^3=3abc
3.已知:abc不等于0,ab+bc=2ac
求证:(1/a)-(1/b)=(1/b)-(1/c).
4.a+b小于0,且满足a^2+2ab+b^2-a-b=2,求(a^3+b^3)/(1-3ab)的值.
5.若(1/a)+(1/b)=(1/c),则证明a^2+b^2+c^2=(a+b-c)^2
6.若a、b为实数,且满足(1/a)-(1/b)=(1/(a+b)),则(b/a)-(a/b)的值是()
A.-1 B.0 C.1/2 D.1
关于化简求值与恒等证明1.已知a+b+c=0.求证:(1)a^3+a^2c+b^2c+b^3=abc(2)a^4+b^4+c^4=2a^2b^2+2b^2c^2+2c^2a^22.已知a+b+c=0,求证:a^3+b^3+c^3=3abc3.已知:abc不等于0,ab+bc=2ac求证:(1/a)-(1/b)=(1/b)-(1/c).4.a+b小于0,
1.(1)左边=a^2(a+c)+b^2(b+c)=-a^2b-b^2a=-ab(a+b)=abc
(2) 左边-右边=(a^2-b^2)^2+c^4-2c^2(a^2+b^2)
=(a+b)^2(a-b)^2+c^2(c^2-2a^2-2b^2)
=c^2[(a-b)^2+c^2-2a^2-2b^2]
=c^2(-a^2-2ab-b^2+c^2)
=c^2[c^2-(a+b)^2]
=c^2(c-a-b)(c+a+b)
=0
2.左边=(a+b)^3-3a^2b-3ab^2+c^3=-c^3-3ab(a+b)+c^3=3abc
3.abc不等于0,ab+bc=2ac两边同时除以abc,整理即可
4.条件整理得:(a+b)^2-(a+b)-2=0
(a+b-2)(a+b+1)=0,由于a+b