And if the lesser term is commensurable in length with the rational (straight line previously) laid out then let (the whole straight line) be called a second binomial (straight line).
The second binomial is a straight line whose length is \[\frac{\alpha}{\sqrt{1-\beta^{\,2}}}+\alpha,\]
where \(\alpha,\beta\) denote positive rational numbers.
Proofs: 1 2 3 4 5 6 7 8
Propositions: 9 10 11