计算或化简求值 (1)(1/4a2b)•(−2ab2)2÷(−0.5a4b5) (2)4x2-(-2x+3)(-2x-3) (3)20102-2009×2011 (4)(a-2b+c)(a+2b-c) (5)[(x+y)2-(x+y)(x+

问题描述:

计算或化简求值
(1)(

1
4
a2b)•(−2ab2)2÷(−0.5a4b5)
(2)4x2-(-2x+3)(-2x-3)
(3)20102-2009×2011 
(4)(a-2b+c)(a+2b-c)
(5)[(x+y)2-(x+y)(x+3y)-5y2]÷(2y),其中x=-2,y=
1
2

(1)原式=14a2b•4a2b4÷(-0.5a4b5)=-2;(2)原式=4x2-(4x2-9)=9;(3)原式=20102-(2010-1)×(2010+1)=20102-(20102-1)=1;(4)原式=a2-(2b-c)2=a2-4b2+4bc-c2;(5)(x2+2xy+y2-x2-3xy-xy-3y2-5y2...