4(x+2) chia hết cho x+1
=>4x+8 chia hết cho x+1
=>(4x+4)+4 chia hết cho x+1
=>4(x+1)+4 chia hết cho x+1 mà 4(x+1) chia hết cho x+1
=>4 chia hết cho x+1
=>x+1\(\in\)Ư(4)
=>x+1 \(\in\) {-4;-2;-1;1;2;4}
=>x \(\in\) {-5;-3;-2;0;1;3}
vậy có 6 số nguyên thỏa mãn
Thanks Youuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu very muchhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh !!!!!