Question

Помогите срочно..
(1 -1/2)*(1 -1/3)
(1 - 1/2)*(1 - 1/3)*(1 -1/4)
1 -12

Answer 1

1-1/2*1-1/3=1/2*2/3=1/3
1-1/2*1-1/3*1-1/4=1/2*2/3*3/4=1/4
1-1/2=1/2