2

Part of 1996 Tuymaada Olympiad

Problems(1)

subset A of real, if a \n A then 1/a and 1-a \in A, also 0,1 \not in A

Source: Tuymaada 1996 p2

Given a finite set of real numbers

A

, not containing

0

1

and possessing the property: if the number a belongs to

A

\frac{1}{a}

1-a

A

. How many numbers are in the set

A

algebraset theorySetsReal