theorem Th67: :: JGRAPH_6:67

for p being Point of (TOP-REAL 2)
for f being Function of (TOP-REAL 2),(TOP-REAL 2) st f = Sq_Circ & p `1 = - 1 & p `2 < 0 holds
( (f . p) `1 < 0 & (f . p) `2 < 0 )