Question

2
K -K +3
------------ € Z
K+1

K€Z

Answer 1

(k²+k-2k+3)/(k+1)∈Z

k+(-2k+3)/(k+1)∈Z

(2k-3)/(k+1)∈z

(2k+2-5)/(k+1)∈Z

2-5/(k+1)∈z

5/(k+1)∈Z

k+1∈D5Z={-5;-1;1;5}

k∈{-6;-2;0;4}

verificare

45/-5; 9/-1;3/1; 15/5 toate∈Z