I don't fathom why this popular Hong Kong mathematics author is discussing hyperbolas and the song lyrics discussed. How do they relate?
The song is called 0614 by Rosa Lee Ka Yee. My Chinese is too rudimentary, but I'm guessing that the song smacks of relationship and romance and longing for a partner?
The book is 數。妳。by W. L. LEE. I have pp 49-52 as shown below.