Statement I : The formula connecting u, v and f for a spherical mirror is valid only for the mirrors whose sizes are very small as compared to their radii of curvature.
Statement II : Laws of reflection are strictly valid for plane surfaces, but not for larger spherical surfaces. [ IIT JEE 2007 ]
While deriving mirror formula for a spherical surface, we consider only paraxial rays as a spherical surface is perfectly focusing mirror only in such cases. Hence we need to take the aperture of the mirror to be very small.
Which implies that the size of the mirror should be very small as compared to their radii of curvature.
So, statement I is correct.
Now, let's talk about the laws of reflection. Laws of reflecting are valid for a spherical surfaces equally as it is for plane surfaces. This law doesn’t have any bias regarding the figure of the surface!