1) 42/2 105/3
21/3 35/5
7/7 7/7
1 1
42 = 2*3*7 105 = 3*5*7
НСД (42; 105) = 3 * 7 = 21
2) 588/2 252/2
294/2 126/2
147/3 63/3
49/7 21/3
7/7 7/7
1 1
588 = 2*2*3*7*7 252 = 2*2*3*3*7
НСД (588; 252) = 2 * 2 * 3 * 7 = 84
3) 680/2 612/2
340/2 306/2
170/2 153/3
85/5 51/3
17/17 17/17
1 1
680 = 2*2*2*5*17 612 = 2*2*3*3*17
НСД (680; 612) = 2 * 2 * 17 = 68