Definition:Apotome/Second Apotome

Definition
Let $a, b \in \R_{>0}$ be two (strictly) positive real numbers such that $a - b$ is an apotome.

Then $a - b$ is a second apotome :
 * $(1): \quad b \in \Q$
 * $(2): \quad \dfrac {\sqrt {a^2 - b^2}} a \in \Q$

where $\Q$ denotes the set of rational numbers.



Also see

 * Definition:First Apotome
 * Definition:Third Apotome
 * Definition:Fourth Apotome
 * Definition:Fifth Apotome
 * Definition:Sixth Apotome