The Shulbasutras of Baudhayana, Apastamba, Katyayana and Manava: With Text, English Translation and Commentary c8.t2.71

The Śulbasūtras of Baudhāyana, Āpastamba, Kātyāyana and Mānava: With Text, English Translation and Commentary c8.t2.71

Let 2a be the side of the square *ABCD*. $OF = a + ⅓ (a √2 - a)$ or r = a [1 + ⅓ (√2 - 1)], where OF = r or r = a/3 (2 + √2)