12=22.3
30=2.3.5
BCNN(12,30)=22.3.5=60
=>BC(12,30)= B(60)=\(\left\{0,60,120,...\right\}\)
B(12)={...;-60;-48;-36;-24;12;0;12;24;36;48;60;...}
B(-30)={...;-60;-30;0;30;60;...}
Do đó: BC(12;-30)={...;-60;0;60}
12=22.3
30=2.3.5
BCNN(12,30)=22.3.5=60
=>BC(12,30)= B(60)={0,60,120,...}{0,60,120,...}