(1)已知a b=2分之3,ab=1,化简(a-2)(b-2)的结果为多少、(2)a-b=1,ab=-2,则(a 1(b-1)=多少
(1)
(a-2)(b-2)
=ab-2(a b) 4
=1-2(3/2) 4
=2
(2)
(a 1)(b-1)
=ab-(a-b)-1
=-2-1-1
=-4
a b-2(a b) 2=3(a b)-34(a b)=5a b=5/41608a 1608b 1=1608(a b) 1=1608*5/4 1=2011
问:绝对值化简已知-4小于X小于0,化简│-X│+│X+4│-│X-4│
答:因为-4<x<0 所以-x>0,x+4>0,x-4<0 原式=-x+(x+4)-(x-4) =-x+8详情>>
答:详情>>