3D Problem
Source: 1986 National High School Mathematics League, Exam One, Problem 7
February 24, 2020
conicsellipse
Problem Statement
Inside a circular column with a bottom surface with radius of , there are two balls with radius of as well. The distance betwen their centers is . Draw a plane that is tangent to both spherical surface, intersect the circular column at a curve . is a ellipse, then the sum of its short axis and long axis is________.