reserve V for RealLinearSpace;
reserve u,u1,u2,v,v1,v2,w,w1,y for VECTOR of V;
reserve a,a1,a2,b,b1,b2,c1,c2 for Real;
reserve x,z for set;
reserve a,b,c,d,a1,a2,b1,c1,d1,d2,p,q for Element of DTrSpace(V,w,y);

theorem
  Gen w,y implies DTrSpace(V,w,y) is MidOrdTrapSpace
proof
  set X = DTrSpace(V,w,y);
  assume
A1: Gen w,y;
  X is MidOrdTrapSpace-like
  by Lm27,Lm28,Lm29,Lm30,Lm31,A1,Lm32,Lm33,Lm34,Lm35,Lm22,Lm23,Lm24,Lm25,Lm26;
  hence thesis;
end;
