(x-k)(x+3)

（x-k)(x+3)/(x+2)≤(x+1)
所以（x-k)(x+3)/(x+2)-(x+1)≤0
所以
[k(x+3+2/k)]/(x+2)>=0
(1) k>0,有(x+3+2/k)]/(x+2)>=0
显然－2>-3-2/k
所以
x>-2,或者x<=-3-2/k
(2)k<0，有(x+3+2/k)]/(x+2)<=0
当k<=-2,有
－3-2/k<-2
所以 －3-2/k<=x<-2
当-2<k<0,有
－3-2/k>-2，
所以
-2<x<=-3-2/k
(3)k=0
x>-2

(x-k)(x+3)/(x+2)≤(x+1)
===>(x-k)(x+3)≤(x+1)(x+2)
===>x^2+(3-k)x-3k≤x^2+3x+2
===>-kx≤2+3k
当k>0时,
原式===>x≥-2/k-3
当k<0时
原式===>x≤-2/k-3

所以x方+(3-k)x-3k小于等于x方+3x+2
所以-kx小于等于2+3k
所以x小于等于（2+3k）/-k

(x-k)(x+3)除以(x+2)小于等于(x+1)的解集
k=0,0<=(x+1) x>=-1
k不等0,
(x-k)(x+3)除以(x+2)小于等于(x+1) (x-k)(x+3)除以(x+2)-(x+1)<=0
(kx+3k+2)/(x+1)>=0, 等价于(kx+3k+2)(x+1)>=0,x不等于-1
k<0,-1<x<=-(3k+2)/k
k>0, -(3k+2)/k<=x<-1