BÀI 7. TA CÓ 1 1 3 3     ĐPCM. 3 ( 3) ( 3) ( 3)X X X X X X X XÁP...

3 ...M  x x  x x   x x     ( 3) ( 3)( 6) ( 12)( 15)= 1 1 1 1 1 13 3 6 ... 12 15xx  x x   x x1 1 15 5   15 ( 15) M ( 15)x x  x x   x x