# The data # (c) copyright 1997, 1998, 2001 Leroy J. Dickey # Three points A, B, and C are on one line L1: [0, 0, 1]. A := [ 1, 0, 0 ] ; B := [ 0, 1, 0 ] ; C := [ 1, -t, 0 ] ; unprotect ( 'D' ) ; unassign ( 'D' ) ; # Three points D, E, and F are on the line L2: [1, -1, 0]. D := [ 0, 0, 1 ] ; E := [ 1, 1, 1 ] ; F := [ 1, 1, u+1 ] ;