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

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Kōti = Sphuta-lambana, and DC = Bhuja = Nāti, it is
argued that the Sphuta-lambana is proportional to
H cos ZV, assuming a maximum value when V coincides
with Z (☉ not being at Z).
Verses 3 and 4. Parallax in longitude based on two
proportions.
Compute the H cosine of ZV, by calculating the
rising time of AV, the Kujyā, Dyujyā and Antyā pertain-
ing to V, as was formulated in the Tripraśnādhikāra, then
H sin V☉, multiplied by 4 and divided by R, and again
multiplied by H cos ZV and divided by R again gives the
parallax in longitude.
Comm. As per the above formula, parallax in longi-
tude equal to ☉D of Fig. 92 is equal to
(4 H sin V☉ × H cos ZV) / R² . This is evidently derived out
of two proportions that the parallax in longitude is
proportional to H sin V☉ as well as H cos ZV. This we
have already derived through modern methods as formula
IV.
Under verse 2. The two proportions are (1) V coin-
ciding with Z, if by H sin V☉ equal to R, we have 4 nādis
as the maximum lambana on the horizon, what shall we
have by an arbitrary H sin V☉? The result is
(4 H sin V☉) / R and (2) V not coinciding with Z, if by
H cos ZV equal to R we have (4 H sin V☉) / R as the
Madhyamalambana, what shall we have for an arbitrary
H cos ZV? The result is
(4 H sin V☉) / R × (H cos ZV) / R as formulated.
First half of verse 5. Alternate method of rectifying
lambana. The Madhyamalambana multiplied by 12 and