diff ( y1 , x , 1 ) = m1 * y2 ; diff ( y2 , x , 2 ) = diff ( y1, x , 1) ; ! Digits := 32; max_terms := 30; ! x_start := 0.5; x_end := 5.0; diff(y1,0,exact_soln_y1(x_start)); diff(y2,0,exact_soln_y2(x_start)); diff(y2,1,exact_soln_y2p(x_start)); glob_max_iter := 20; ! exact_soln_y1 := proc(x) return( - cos(x)); end; exact_soln_y2 := proc(x) return( - sin(x)); end; exact_soln_y2p := proc(x) return( - cos(x)); end;