Question

已知a.b互为相反数,c.d互为倒数,|m |=1,求二分之一（a+b-1）+3cd-2m的值

Answer 1

二分之一（a+b-1）+3cd-2m

=(0-1)/2 + 3* 1 - 2*1 或 =(0-1)/2 + 3* 1 +2*1

= -1/2 +3 -2 = -1/2 +3 +2

= 1/2 = 9/2