试题:
计算
(1)2a b2 (ab-3a2 );              
(2)(-2x)2-(2x-2)(2x+1)
(3)2x(2x-3y)-(2x-y)2;           
(4)20112-2010×2012(用简便方法计算).

答案:

我来补答
(1)2a b2 (ab-3a2 )              
=2a2b3-6a3b2

(2)(-2x)2-(2x-2)(2x+1)
=4x2-4x2-2x+4x+2
=2x+2;

(3)2x(2x-3y)-(2x-y)2
=4x2-6xy-(4x2-4xy+y2
=4x2-6xy-4x2+4xy-y2
=-2xy-y2

(4)20112-2010×2012
=20112-(2011+1)×
=20112-20112+1
=1.
 
 
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