Surya Siddhanta
कोटिज्यया विभज्याप्ते छायाकर्णाव् अहर्दले । क्रान्तिज्या विषुवत्कर्णगुणाप्ता शङ्कुजीवया॥
The sine of the Sun's declination multiplied by the equinoctial hypothenuse and divided by 12 gives the sine of the Sun's amplitude. This sine multiplied by the hypothenuse of the Gnomonic shadow at noon, and divided by the Radius, becomes the sine of amplitude reduced to the shadow's hypothenuse.
english translation
koTijyayA vibhajyApte chAyAkarNAv ahardale । krAntijyA viSuvatkarNaguNAptA zaGkujIvayA॥
hk transliteration by Sanscript