(a) Starting from appropriate similar triangles in the ray diagram for a concave spherical mirror, derive the mirror equation v1+u1=f1. In your derivation, clearly show where the condition f=2R is used.
(b) Using the result obtained in part (a), prove that when the object is placed at the centre of curvature C (i.e., u=−R), the image is formed at the same point C (that is, v=−R), and explain the nature and magnification of this image.