若a b互为相反数,c d互为倒数.2008a-2007cd+2008b=
问题描述:
若a b互为相反数,c d互为倒数.2008a-2007cd+2008b=
答
a b互为相反数,a+b=0
c d互为倒数,c*d=1
2008a-2007cd+2008b
=2008(a+b)-2007cd
=0-2007
=-2007