若a<-b<1,化简[(a+b)/(b+1)]的绝对值-(a+b)的绝对值/(b+1)÷(a+b)/(b+1)的值(求过程)
问题描述:
若a<-b<1,化简[(a+b)/(b+1)]的绝对值-(a+b)的绝对值/(b+1)÷(a+b)/(b+1)的值(求过程)
答
(x+y)(x-y)-(x+y)=0
(x+y)(x-y-1)=0
若x-y-1=0
y=x-1
则4x^2-x^2+2x-1+2x-x+1=0
3x^2-3x=0
3x(x-1)=0
x=0,x=1
y=x-1
若x+y=0
y=-x
则4x^2-x^2+2x+x=0
3x^2+3x=3x(x+1)=0
x=0,x=-1
y=-x
所以
x=0,y=-1
x=1,y=0
x=0,y=0
x=-1,y=1
答
a