计算:
(1);
(2)(-4)2011×0.252011+(-0.125)2011×82012;
(3)化简,求值:y(x+y)+(x+y)(x-y)-x2,其中x=-2,y=.
网友回答
解:(1);
=6-1+,
=5;
(2)(-4)2011×0.252011+(-0.125)2011×82012;
=,
=-1-8,
=-9;
(3)解:y(x+y)+(x+y)(x-y)-x2,
=xy+y2+x2-y2-x2=xy,
当x=-2,y=时,
原式=-2×=-1.
解析分析:(1)利用零指数幂以及二次根式运算法则首先化简,进而利用有理数混合运算求出即可;
(2)先把(-4)2011×0.252011+(-0.125)2011×82012化为的形式,再去小括号,从而得出