theorem Th25: :: JGRAPH_6:25

for Kb, Cb being Subset of (TOP-REAL 2) st Kb = { p where p is Point of (TOP-REAL 2) : ( - 1 < p `1 & p `1 < 1 & - 1 < p `2 & p `2 < 1 ) } & Cb = { p2 where p2 is Point of (TOP-REAL 2) : |.p2.| < 1 } holds
Sq_Circ .: Kb = Cb