Yes, you are right. I actually discovered my mistake myself while lying awake at 3 AM this morning trying to distract my mind from distressing thoughts re: the fate of my poor country with math problems. In a fit of temporary (I hope) insanity I had been captured by the notion that not only the point 1,1 needed to be included in the shaded area but 0,1 and 1,0 also. How, at this late date, could I get to thinking that? You will have to take that up with the guy upstairs. I know not.