I am an undergraduate student and I study mathematics by myself. I have studied Rudin’s Real Analysis, some linear algebra and of course calculus. Recently I realized that I forgot many things that I studied in analytic geometry, such as the conic sections, the equation of an ellipse (and all conic section in general especially the 3D version of them hyperbolic paraboloid, paraboloid and ellipsoid ), how to form a plane equation in three dimensions with certain data and many theorems and their proof.
I feel frustrated because analytic geometry was one of my favourite subjects and I am willing to revisit it again just for fun, but I have a problem I learned most of analytic geometry from calculus books like Thomas’ Calculus and now when I come back to analytic geometry from that book, it seems very basic and too easy. I don’t know how to explain this, but reading Thomas’ Calculus after reading Rudin’s Real Analysis feels very weird and a waste of time. So I want to ask if there are more advanced books for analytic geometry I should use or should I just stick with Thomas’ Calculus and learn from that book? Or should I look for another elementary book for analytic geometry?
