diff ( y , x , 1 ) = arctan(sqrt(0.1 * x + 0.2)); ! Digits := 32; max_terms := 30; ! x_start := -1.0; x_end := 0.5 ; diff(y,0,exact_soln_y(x_start)); glob_look_poles := true; glob_max_iter := 1000000; glob_display_interval := 0.1; glob_max_minutes := 10; glob_max_h := 0.0001; ! exact_soln_y := proc(x) return(10.0 * (0.1 * x + 0.2) * arctan(sqrt ( 0.1 * x + 0.2)) - 10.0 * sqrt( 0.1 * x + 0.2) + 10.0 * arctan(sqrt( 0.1 * x + 0.2))); end;