Question

why convex mirror is used in real view mirror and not concave mirror, explain

Answer 1

A convex mirror gives a much wider field of view than a plane mirror. Unfortunately, the reflected image is distorted making near objects appear further away than they actually are. Convex rear view mirrors are only used on the passenger side, so the driver can see a much wider rear view field of view.

Answer 2

Because A convex mirror is used as rear view mirror because they form erect, virtual, and diminished images which allow the driver to view a large area in a small mirror.