拆项后分组求解(X的立方)+X-2=(X的立方)-2X+1=(X的立方)-(X的平方)+2=

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拆项后分组求解(X的立方)+X-2=(X的立方)-2X+1=(X的立方)-(X的平方)+2=

拆项后分组求解(X的立方)+X-2=(X的立方)-2X+1=(X的立方)-(X的平方)+2=
拆项后分组求解
(X的立方)+X-2=
(X的立方)-2X+1=
(X的立方)-(X的平方)+2=

拆项后分组求解(X的立方)+X-2=(X的立方)-2X+1=(X的立方)-(X的平方)+2=
x^3+x-2
=x^3-1+x-1
=(x-1)(x^2+x+1)+(x-1)
=(x-1)(x^2+x+1+1)
=(x-1)(x^2+x+2)
x^3-2x+1
=x^3-x-x+1
=x(x^2-1)-(x-1)
=x(x-1)(x+1)-(x-1)
=(x-1)(x^2+x-1)
x^3-x^2+2
=x^3+1-x^2+1
=(x+1)(x^2-x+1)-(x-1)(x+1)
=(x+1)[(x^2-x+1)-(x-1)]
=(x+1)[x^2-x+1-x+1]
=(x+1)[x^2-2x]
=x(x+1)(x-2)