Question

2004.05✖️1997.05➖2001.05✖️1999.05简便算法

2004.05ﾁ7ﾾ0ﾄ1ﾂ51997.05ﾁ7ￊ82001.05ﾁ7ﾾ0ﾄ1ﾂ51999.05简便算法

Answer 1

解：模胡清原旦前式=2004.05×1997.05-2001.05×1999.05
=2004.05×1997.05-（2004.05-3）（1997.05+2）做春
=-2004.05×2+1997.05×3+6
=-2000×2-4.05×2+2000×3-2.95×3+6
=2000-8.1-8.85+6
=2006-16.95
=1989.05

Answer 2

简或举猜便计答运算
2004.05×1997.05-2001.05×1999.05
=(2001.05＋3)×1997.05－2001.05×1999.05
=2001.05×1997.05＋3×1997.05－2001.05×1999.05
=[2001.05×1997.05－2001.05×1999.05]＋3×1997.05
=2001.05×(1997.05－1999.05)＋3×1997.05
=2001.05×(－2)＋3×1997.05
=2001.05×[1－3]＋衫型3×1997.05
=2001.05－3×2001.05＋3×1997.05
=2001.05－3×4
=2001.05－12
=1989.05