问题
解答题
-x(2-x)(-x-2)-(2x-1)2+(x-2)(x2+2x+4).
答案
原式=x(2-x)(x+2)-(4x2-4x+1)+x3+2x2+4x-2x2-4x-8
=4x-x3-4x2+4x-1+x3+2x2+4x-2x2-4x-8
=-4x2+8x-9.
-x(2-x)(-x-2)-(2x-1)2+(x-2)(x2+2x+4).
原式=x(2-x)(x+2)-(4x2-4x+1)+x3+2x2+4x-2x2-4x-8
=4x-x3-4x2+4x-1+x3+2x2+4x-2x2-4x-8
=-4x2+8x-9.