Question

1/2+5/7; 4/5+1/6; 1/2-1/3; 1/3-1/4; 2/3-1/5; 5/7-2/3 решите пож

Answer 1

Ответ на первый пример на рисунке

Answer 2

1/2+5/7= 17/14= 1. 3/14
4/5+1/6=29/30
1/2-1/3=1/6
1/3-1/4=1/12
2/3-1/5=7/15
5/7-2/3= 1/21

Answer 3

1/2 + 5/7 = (1*7 + 2*5) / (2*7) = 17/14

4/5 + 1/6 = (4*6 + 1*5) / (5*6) = 29/30

1/2 - 1/3 = (3 - 2) / (2*3) = 1/6

1/3 - 1/4 = (4 - 3) / (3*4) = 1/12

2/3 - 1/5 = (10 - 3) / (3*5) = 7/15

5/7 - 2/3 = (15 - 14) / (7*3) = 1/21

Разрешим уравнение: 1/2 + 5/7 - 2/3 = (1*42 + 5*30 - 2*28) / (2*7*3) = (42 + 150 - 56) / 42 = 136/42 = 68/21