问题
解答题
计算 (1)(-2011)0+(-3)2-(
(3)(x2+2x-1)(x-1)(4)(x-2y)2-(x+2y)(x-2y) |
答案
(1)(-2011)0+(-3)2-(
)-1,1 4
=1+9-4,
=6;
(2)m2•(-n)3•(mn)4,
=-m2n3m4n4,
=-m6n7;
(3)(x2+2x-1)(x-1),
=x3+2x2-x-x2-2x+1,
=x3+x2-3x+1;
(4)(x-2y)2-(x+2y)(x-2y),
=x2-4xy+4y2-(x2-4y2),
=x2-4xy+4y2-x2+4y2,
=-4xy+8y2.