1. The problem statement, all variables and given/known data Can you move the object and the lens in such a way that the image is virtual? If so, relate where the object is with respect to the focal length of the lens 2. Relevant equations 1/f =1/p +1/q or f = (p + q)^-1 3. The attempt at a solution What I can do, is add a convex lens into my lab environment. I can use the source of the light and shine it directly at the center of the convex lens. What happens is that the light is bent in some way (can't descibe it), but I know that the light does in fact go through the convex lens, so, by defintion the image is virtual. I know that it is possible to get a virtual image, but how would I relate the objects positon? I know that the mathematical phrase 'with respect' is a d/dx. But this is an algebra based course, so having to use leibniz (however its spelt) is confusing. Could someone help with this? Thanks in advance!