若m,n互为相反数,p,q互为倒数,求|m-2+n|+二分之pq的值
问题描述：
若m,n互为相反数,p,q互为倒数,求|m-2+n|+二分之pq的值
答
m,n互为相反数,p,q互为倒数
m+n=0 pq=1
|m-2+n|+二分之pq
=|-2|+1/2
=2+1/2
=5/2 (2分之5)