! [A,B]: (point(A) & point(B) & A!=B)
? [L1,D] : (line(L1) & point(D) & inc_po_l(A,L1) & inc_po_l(B,L1) & ninc_po_l(D,L1))
? [E] : (point(E) & bet(B,D,E))
? [F] : (point(F) & bet(A,E,F))
(ncol(A,B,E))
? [L2] : (line(L2) & inc_po_l(F,L2) & inc_po_l(D,L2))
(ninc_po_l(A,L2))
? [P] : (plane(P) & inc_po_pl(A,P) & inc_po_pl(B,P) & inc_po_pl(E,P))
(inc_po_pl(D,P))
(inc_po_pl(F,P))
(inc_l_pl(L2,P))
(ninc_po_l(A,L2))
(ninc_po_l(B,L2))
(ninc_po_l(E,L2))
(cut(L2,B,E))
? [L3] : (line(L3) & pash(A,B,E,L2,P) & E!=A & inc_po_l(E,L3) & inc_po_l(A,L3))
? [X] : (point(X) & bet(A,X,B))
   


