See below.
The following are the guidelines for creating ray diagrams for the generation of an image by a concave mirror:
Rule 1: If the incident ray is parallel to the major axis, the reflected ray will pass through the concave mirror's focus.
The reflected ray is parallel to the principal axis if the incident ray passes through the focus of the concave mirror.
Rule 3: If the incident ray passes through the concave mirror's center of curvature, the reflected ray follows the same path.
Hope this helps!
