利用因式分解计算:20112-2012×2010=______.
原式=20112-(2011+1)×=20112-(20112-1)=20112-20112+1=1.
故答案为:1
As is often the case, the fact that something is cheap doesn’t _____ mean it’s of low quality.
A.necessarily
B.usually
C.certainly
D.mostly
磁致伸缩效应