{3x^2(a^2+b^2)-3a^2b^2+3[x^2+(a+b)x+ab]*[x(x-a)-b(x-a)]}/2x^2其中x=2先化简,

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{3x^2(a^2+b^2)-3a^2b^2+3[x^2+(a+b)x+ab]*[x(x-a)-b(x-a)]}/2x^2其中x=2先化简,
{3x^2(a^2+b^2)-3a^2b^2+3[x^2+(a+b)x+ab]*[x(x-a)-b(x-a)]}/2x^2其中x=2先化简,

{3x^2(a^2+b^2)-3a^2b^2+3[x^2+(a+b)x+ab]*[x(x-a)-b(x-a)]}/2x^2其中x=2先化简,
{3x^2(a^2+b^2)-3a^2b^2+3[x^2+(a+b)x+ab]*[x(x-a)-b(x-a)]}/2x^2
=3/2{x^2a^2+x^2b^2-a^2b^2+[x^2+(a+b)x+ab]*[x^2-(a+b)x+ab]}/x^2
=3/2{x^2a^2+x^2b^2-a^2b^2+[(x^2+ab)^2-(a+b)^2x^2]}/x^2
=3/2{(a^2+b^2)x^2-a^2b^2+x^4+2a^2b^2x^2+a^2b^2-(a+b)^2x^2]}/x^2
=3/2{x^4+x^2[a^2+b^2+2a^2b^2-a^2-b^2-2ab]}/x^2
=3/2[x^4+(2a^2b^2-2ab)x^2]/x^2
=3/2(x^2+2a^2b^2-2ab)
若x=2
上式=3/2(4+2a^2b^2-2ab)=6+3a^2b^2-3ab