Final answer:
The mirror setting that allows drivers not to see the sides of their vehicle is called a wide-angle view, typically achieved with convex mirrors, which can make objects appear farther away than they are.
Step-by-step explanation:
When adjusting the mirror so that the driver will not see the left and right sides of the vehicle when glancing at the outside mirrors, the setting is referred to as a wide-angle view. This view is typically achieved using a convex mirror, which is a type of diverging mirror. These mirrors are often used for rear-view mirrors in vehicles because they provide a wide field of view, allowing the driver to see more area behind the vehicle.
However, the main disadvantage of a convex mirror compared to a flat one is that objects in the mirror may appear to be farther away than they actually are. This is why you might see a warning that says, "Objects in mirror are closer than they appear."