Сократить дробь: 3*14*62/31*10*27 56*15*38/75*16*57 6ab-6b/12

1) (3 * 14 * 62) / (31 * 10 * 27) = (3 * 14) / (10 * 27) * 62/31 =

= (3 * 7 * 2) / (10 * 3 * 9) * 2/1 = (7 * 2) / (10 * 9) * 2 * 3/3 =

= (7 * 2) / (5 * 2 * 9) * 2 * 1 = 7 / (5 * 9) * 2/2 * 2 = 7/45 * 2 = 14/45;

2) (56 * 15 * 38) / (75 * 16 * 57) = (56 * 38) / (16 * 57) * 15/75 =

= (7 * 8 * 2 * 19) / (2 * 8 * 57) * 1/5 = (7 * 19) / 57 * 1/5 * (8 * 2) / (8 * 2) =

= (7 * 19) / (3 * 19) * 1/5 * 1 = 7/3 * 1/5 = 7/15;

3) В числителе надо вынести за скобки:

(6 * a * b - 6 * b) / 12 = 6 * b * (a - 1) / 12 = 6 * b * (a - 1) / (2 * 6) =

= b * (a - 1) / 2.