सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

257 In the parallel great circle, the Equator we have therefore Antyā = Charajyā + R (already derived). Verse 35. Antyā = (Hṛti × R) / (H cos δ) = (Hṛti × Charajyā) / Kujyā and ∴ Hṛti = (Antyā × H cos δ) / R = (Antyā × Kujyā) / Charajyā by what is called Guṇa-ccheda-Viparyaya ie. alternando. Comm. Evident. Verse 36. To obtain Dinārdha-Śaṅku from Antyā and Hṛti (Antyā × un-maṇḍala Śaṅku) / Charajyā = (Hṛti × 12) / K = Dinārdha- Śaṅku. Comm. The second formula is derived from the similarity of △ Ao₄a (fig.) with the first latitudinal triangle. From the similarity of Aao₄, Ddo₄ fig. 39, Ao₄/Do₄ = Aa / Dd ∴ Aa = (Hṛti × unmaṇḍala-Śaṅku) / Kujyā . But Aa = Dinārdha-Śaṅku ∴ Dinārdha Śaṅku = (Hṛti × U.S.) / Kujyā (U. S. = Un- maṇḍala-Śaṅku.) But Hṛti / Kujyā = Antyā / Charajyā ∴ D.S. (Dinārdha-Śaṅku) = Charajyā / Antyā × U.S. = (Hṛti × 12) / K VIII. Verse 37. Meridian Zenith distance. Agrā ± (Hṛti × bhuja of a lat. triangle) / (Karṇa of a lat. triangle) = H sin z where z is the meridian zenith distance. 33