Why do we use concave mirrors for shaving and convex mirrors for rearview in cars?

Concave mirrors are used for shaving because when an object (your face) is placed between the pole and the principal focus of a concave mirror, it forms a magnified, erect, and virtual image. This allows you to see a larger, clearer view of your face for precise shaving. Convex mirrors are preferred as rearview mirrors in vehicles because they always form a diminished, erect, and virtual image, regardless of the object's distance. More importantly, they have a wider field of view compared to plane or concave mirrors, enabling the driver to see a much larger area behind the car, which is crucial for safe driving.