2008*2009分之2008简算

问题描述:

2008*2009分之2008简算

2008×2008/2009
=(2009-1)×2008/2009
或者:2008×(1-1/2009)
=2008-2008/2009
=2007又1/2009

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