reserve a,b,c,x,y,z for object,X,Y,Z for set,
  n for Nat,
  i,j for Integer,
  r,r1,r2,r3,s for Real,
  c1,c2 for Complex,
  p for Point of TOP-REAL n;

theorem Th45:
  for s being Real, p being Point of TOP-REAL 2 holds
  (Rotate(s)).p = 0.TOP-REAL 2 implies p = 0.TOP-REAL 2
  proof
    let s be Real;
    let p be Point of T2;
    |.p.| = |.(Rotate(s)).p.| by Th41;
    hence thesis by TOPRNS_1:23,24;
  end;
