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

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Fig. 44
Verse 41. Alternate method of obtaining K
101530/H sin λ = para (say) where λ is the Sāyana
longitude of the Sun ; then, (Para × k) / s = K where K is
un-mandala-Karṇa
First half of Verse 42. To obtain K when the Sun is
on the prime-vertical— Para × s/k = Samavṛttakarṇa.
Comm. From fig. 19, from the similarity of triangles
BD ☉ and CMA, B ☉ / CA = ☉ D / AM ie. ☉ D = (B ☉ × AM) / CA ie.
H sin δ = (H sin λ H sin ω) / R (a)
Then consider the similarity of the first and the sixth
latitudinal triangles ; then Unmandala Sanku / Krāntijyā = s / k (b)
where s is the equinoctial shadow and k the Viṣuvat-
Karṇa. Again taking that ☉ the Sun lies on the unman-