reserve x,y for set,
  i for Nat;
reserve V for non empty CLSStruct,
  u,v,v1,v2,v3 for VECTOR of V,
  A for Subset of V,
  l, l1, l2 for C_Linear_Combination of A,
  x,y,y1,y2 for set,
  a,b for Complex,
  F for FinSequence of the carrier of V,
  f for Function of the carrier of V, COMPLEX;
reserve K,L,L1,L2,L3 for C_Linear_Combination of V;

theorem
  for V being Abelian add-associative right_zeroed right_complementable
non empty CLSStruct, l being C_Linear_Combination of {}(the carrier of V) holds
  Sum l = 0.V
proof
  let V be Abelian add-associative right_zeroed right_complementable non empty
  CLSStruct;
  let l be C_Linear_Combination of {}(the carrier of V);
  l = ZeroCLC V by Th5;
  hence thesis by Th11;
end;
