1.已知x^2+x-1=0,求x^3+2x^2+3 的值.2.(a-2b+3c)(a+2b-3c)=(________)^2-(_______)^2=_______3.(x+y)(x^2-xy+y^2)=___________4.(x-y)(x^2+xy+y^2)=___________5.x(x+1)(x+2)(x+3)=___________6.已知a≠b,且a(a+2)=b(b+2),求a+b的值.备注:(^为平方

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1.已知x^2+x-1=0,求x^3+2x^2+3的值.2.(a-2b+3c)(a+2b-3c)=(________)^2-(_______)^2=_______3.(x+y)(x^2-xy+y^2)

1.已知x^2+x-1=0,求x^3+2x^2+3 的值.2.(a-2b+3c)(a+2b-3c)=(________)^2-(_______)^2=_______3.(x+y)(x^2-xy+y^2)=___________4.(x-y)(x^2+xy+y^2)=___________5.x(x+1)(x+2)(x+3)=___________6.已知a≠b,且a(a+2)=b(b+2),求a+b的值.备注:(^为平方
1.已知x^2+x-1=0,求x^3+2x^2+3 的值.
2.(a-2b+3c)(a+2b-3c)=(________)^2-(_______)^2=_______
3.(x+y)(x^2-xy+y^2)=___________
4.(x-y)(x^2+xy+y^2)=___________
5.x(x+1)(x+2)(x+3)=___________
6.已知a≠b,且a(a+2)=b(b+2),求a+b的值.
备注:(^为平方号!)

1.已知x^2+x-1=0,求x^3+2x^2+3 的值.2.(a-2b+3c)(a+2b-3c)=(________)^2-(_______)^2=_______3.(x+y)(x^2-xy+y^2)=___________4.(x-y)(x^2+xy+y^2)=___________5.x(x+1)(x+2)(x+3)=___________6.已知a≠b,且a(a+2)=b(b+2),求a+b的值.备注:(^为平方
1.
x^2+x-1=0 可得 x^2=1-x
x^3+2x^2+3=x^3-1+2x^2+4=(x-1)(x^2+x-1+2)+2x^2+4
=2(x-1)+2x^2+4=2x^2+2x-2+4
=4
2.(a-2b+3c)(a+2b-3c)=(a)^2-(2b-3c)^2=a^2-4b^2+12bc-9c^2
3.(x+y)(x^2-xy+y^2)=x^3+y^3
4.(x-y)(x^2+xy+y^2)=x^3-y^3
5.x(x+1)(x+2)(x+3)=x^4+6x^3+11x^2+6x
6.已知a≠b,且a(a+2)=b(b+2),求a+b的值.
拆开,分解因式得2(a-b)=-(a-b)(a+b)
a+b=-2

第一题是4
第六题是0