Question

Some rearview mirrors produce images of cars to your rear that are smaller than they would be if the mirror were flat. are the mirrors concave or convex?

Answer 1

They are convex mirrors.
These differ from planes and concaves in the way they reflect light.The concaves cause the light to converge towards the focus, while the convex ones make the light rays diverge towards the outside, granting a wider field of vision, but in which the objects, or in this case the vehicles, see more small of what they are. That is what gives the impression that the cars are further away than they actually are.