1. The problem statement, all variables and given/known data I have a concave lens where f < do < R. I have to provide a ray tracing diagram. 3. The attempt at a solution I drew the focal ray through the focus and parallel to the principal axis. I drew the principal ray parallel to the principal axis then through the focus. I drew a dashed line from the center past the object tip and to the lens. This leads to a diagram where there are no converging lines. However, if I arbitrarily choose some numbers to confirm this... this is where I get confused. I'll choose a focal length (f) of 5cm. This means that R must be 2f. So, R = 10cm. I'll choose an so between 5cm and 10cm of 7.5cm. Given that: 1/so + 1/si = 1/f 1/0.075m + 1/si = 1/0.05m si = 0.15m M = -0.15m/0.075m = -2 This is telling me that I have a real image that is inverted and magnified by a factor of two. Confused. Any help would be appreciated.