KX=4-X,(K+1)X=4,X=1,X=2,X=4 X=1,K=3 X=2,K=1 X=4,K=0 KX=4-X,(K+1)X=4,X=1,X=2,X=4 X=1,K=3 X=2,K=1 X=4,K=0
(k+1)x=4,当k=0,1,3时,有整数解
(K+1)X=4X=4/K+1所以k=0,1,3
k=0,1,3