用简便方法计算:
(1)(0.2)2008×(-25)1005;
(2)19962-16.
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解:(1)(0.2)2008×(-25)1005,
=(0.2)2008×(-52010),
=(0.2)2008×(-52008)×52,
=-(0.2×5)2008×25,
=-25;
(2)19962-16,
=19962-42,
=(1996+4)(1996-4),
=2000×1992,
=3984000.
解析分析:(1)把(-25)1005转化为-52010=-52008×52,再运用积的乘方计算;
(2)因为16=42,所以运用平方差公式计算即可.
点评:本题考查了积的乘方,平方差公式,逆用性质和公式使计算更加简便.