2009×2008-2008×2007-2008简便运算要是简便的运算,最后答案我知道等于2008,

来源:学生作业学帮网 编辑:学帮网 时间:2024/05/30 06:43:06

2009×2008-2008×2007-2008简便运算
要是简便的运算,最后答案我知道等于2008,

2009×2008-2008×2007-2008
=2009×2008-2007×2008-1×2008
=(2009-2007-1)×2008
=1×2008
=2008

2009×2008-2008×2007-2008
=2009×2008-2008×2007-2008×1
=(2009-2007-1)×2008
=2008

=(2009-2007-1)×2008
=1×2008
=2008

2009×2008-2008×2007-2008
=2008×(2009-2007-1) 提取公因式2008
=2008×1
=2008