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

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H sin β = (H sin λ H sin i) / R where β is the latitude required,
i the maximum latitude and λ the arc of the planetary
orbit intercepted between the nearer node and the planet.
Since β and i are small H sin β and H sin i could be taken
to be β and i. Hence we have β = (i × H sin λ) / R . Since
this value is had at the distance of the Śīghrakarṇa, its
value at a distance of R should be given by
β = (i H sin λ) / R × R / K = (i H sin λ) / K as formulated.
Verse 3. √(R² - H sin² v) is called Yaṣṭi where v is
Āyanavalana. The latitude β of the planet multiplied by
Yaṣṭi and divided by R or multiplied by H cos δ where δ
is the declination of the point whose longitude is 90 + λ,
λ being that of the planet and divided by R gives the value
of the rectified latitude which could be added to the
declination of the foot of the latitude to give what we say
the modern declination of the planet.
[Diagram: Spherical geometry diagram showing points P, P', K, R, R', B, B', M, M', S, L, N, ω, γ]
Fig. 107