若n-m=-3,则m-n= ( ),-1+m-n=( ),4-2m+2n=( )
问题描述:
若n-m=-3,则m-n= ( ),-1+m-n=( ),4-2m+2n=( )
答
若n-m=-3,则m-n= ( 3),-1+m-n=(-1+3=2 ),4-2m+2n=4-2(m-n)=4-2*3=-2
若n-m=-3,则m-n= ( ),-1+m-n=( ),4-2m+2n=( )
若n-m=-3,则m-n= ( 3),-1+m-n=(-1+3=2 ),4-2m+2n=4-2(m-n)=4-2*3=-2