関連ワード:
focal length in concave mirror is always negative or positive focal length of convex mirror is always negative or positive focal length of concave lens is always negative or positive focal length in concave mirror is negative or positive focal length of convex lens is always negative or positive focal length in convex mirror is negative or positive focal length in concave lens is negative or positive focal length in convex lens is negative or positive object distance in concave lens is always negative or positive
