reserve a,b,p,x,x9,x1,x19,x2,y,y9,y1,y19,y2,z,z9,z1,z2 for object,
   X,X9,Y,Y9,Z,Z9 for set;
reserve A,D,D9 for non empty set;
reserve f,g,h for Function;
reserve A,B for set;
reserve x,y,i,j,k for object;

theorem Th98:
  f c= g implies g+*f = g
proof
  assume
A1: f c= g;
  then f tolerates g by PARTFUN1:54;
  hence g+*f = f\/ g by Th30
    .= g by A1,XBOOLE_1:12;
end;
