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计算1.(3a+2)^2 2.(a+1)(a-1)(a^2-1) 解方程8x^3+3(x-1)(x+1)-(3X+2)(

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计算1.(3a+2)^2 2.(a+1)(a-1)(a^2-1) 解方程8x^3+3(x-1)(x+1)-(3X+2)(x-3)=(1+2X+4x^2)(2X-1)
计算1.(3a+2)^2
2.(a+1)(a-1)(a^2-1)
解方程8x^3+3(x-1)(x+1)-(3X+2)(x-3)=(1+2X+4x^2)(2X-1)
1.(3a+2)^2
=9a^2+12a+4
2.(a+1)(a-1)(a^2-1)
=(a^2-1)(a^2-1)
=(a^2-1)^2
=a^4-2a^2+1
8x^3+3(x-1)(x+1)-(3X+2)(x-3)=(1+2X+4x^2)(2X-1)
8x^3+3(x-1)(x+1)-(3X+2)(x-3)=8x^3-1
3(x-1)(x+1)-(3X+2)(x-3)=-1
3(x^2-1)-(3x^2--x-6)=-1
3x^2-3-3x^2+x+6=-1
x+3=-1
x=-4
再问: 你确定最后一题正确??
再答: 8x^3+3(x-1)(x+1)-(3X+2)(x-3)=(1+2X+4x^2)(2X-1) 8x^3+3(x-1)(x+1)-(3X+2)(x-3)=8x^3-1 3(x-1)(x+1)-(3X+2)(x-3)=-1 3(x^2-1)-(3x^2-7x-6)=-1 3x^2-3-3x^2+7x+6=-1 7x+3=-1 7x=-4 x=-4/7
再问: .. 嗯 .满意了.!!