1.(X+1)(X+2)(X+3)
=(X+2-1)(X+2)(X+2+1)
=(X+2)([(X+2)^2-1)
=(X+2)^3-(X+2)
=X^3+6X^2+12X+4-X-2
=X^3+6X^2+11X+2
2.(X-Y)平方-(X+Y)(X-Y)
=(X-Y)^2-(X^2-Y^2)
=X^2-2XY+Y^2-X^2+Y^2
=2Y^2-2XY
3.(X+1)(X-2)(X-3)
=(X-1+2)(X-2)(X-1-2)
=(X-2)[(X-1)^2-4]
=(X-2)(X^2-2X-3)
=X^3-2X^2-3X-2X^2+4X+6
=X^3-4X^2+X+6以上有过程
4.( 4x)(2x2+3x+1)
5.x(x2+3)+x2(x 3) 3x(x2 x 1)
6.xn+1(xn xn-1+x2+n)
7.(x2 x+1)m(x x2 1)2n(x x2 1)
就找到这几个 你在自己找找吧
