|I just realized a mistake. If the taskbar can cover the gap, it's not a problem with the resolution.|
Right-click on your desktop, select properties, and click the Desktop tab. Look over to the right side of the dialog box and you should see something that says "Position". Is it on stretch? Is the gap still visible when you are using your browser or any other program?
You could try right-clicking on your desktop > Graphics Properties> Panel Fit> and make sure "Full Screen (No Border)" is checked.
Also make sure the wallpaper you choose is the same resolution as your screen.
"If P = NP, then the world would be a profoundly different place than we usually assume it to be. There would be no special value in "creative leaps," no fundamental gap between solving a problem and recognizing the solution once it's found. Everyone who could appreciate a symphony would be Mozart; everyone who could follow a step-by-step argument would be Gauss..."