theorem Th10: :: JORDAN5C:10
for P being Subset of (TOP-REAL 2)
for p1, p2, q1 being Point of (TOP-REAL 2) st P is_an_arc_of p1,p2 & q1 in P holds
( LE p1,q1,P,p1,p2 & LE q1,p2,P,p1,p2 )