2008+2007×20092008×2009−1.

问题描述:

2008+2007×2009
2008×2009−1

2008+2007×2009
2008×2009−1

=
2008+2007×(2008+1)
2008×(2008+1)−1

=
2008+2007×2008+2007
2008×2008+2008−1

=
2008×2008+2007
2008×2008+2007

=1.