用简便方法计算: (1)20142+16-8×2014; (2)9992-1002×998.
问题描述:
用简便方法计算:
(1)20142+16-8×2014;
(2)9992-1002×998.
答
(1)原式=20142-2×2014×4+42
=(2014-4)2
=20102
=4040100;
(2)原式=9992-(1000+2)(1000-2)
=9992-10002+4
=(999+1000)(999-1000)+4
=-1999+4
=-1995.