aries . ▁The ▁work ▁was ▁written ▁in ▁verse ▁couple ts ▁and ▁de als ▁with ▁mathematics ▁and ▁astronom y . ▁Following ▁an ▁introduction ▁that ▁contains ▁astronom ical ▁tables ▁and ▁A ry ab h ata ' s ▁system ▁of ▁ph on em ic ▁number ▁notation ▁in ▁which ▁numbers ▁are ▁represented ▁by ▁a ▁con son ant - v owel ▁mon os yll able , ▁the ▁work ▁is ▁divided ▁into ▁three ▁sections : ▁Gan ita ▁(" Math emat ics "), ▁K ala - k ri ya ▁(" Time ▁Calcul ations "), ▁and ▁G ola ▁(" S phere "). ▁ ▁In ▁Gan ita ▁A ry ab h ata ▁names ▁the ▁first ▁ 1 0 ▁decimal ▁places ▁and ▁gives ▁algorithms ▁for ▁obtain ing ▁square ▁and ▁cub ic ▁roots , ▁using ▁the ▁decimal ▁number ▁system . ▁Then ▁he ▁tre ats ▁geometric ▁measurements — emp loy ing ▁ 6 2 , 8 3 2 / 2 0 , 0 0 0 ▁(= ▁ 3 . 1 4 1 6 ) ▁for ▁ π — and ▁develop s ▁properties ▁of ▁similar ▁right - ang led ▁tri angles ▁and ▁of ▁two ▁intersect ing ▁circles . ▁Using ▁the ▁P yth ag ore an ▁theorem , ▁he ▁obtained ▁one ▁of ▁the ▁two ▁methods ▁for ▁construct ing ▁his ▁table ▁of ▁s ines . ▁He ▁also ▁realized ▁that ▁second - order ▁s ine ▁difference ▁is ▁proportional ▁to ▁s ine . ▁Mathemat ical ▁series , ▁quadratic ▁equations , ▁comp ound ▁interest ▁( in vol ving ▁a ▁quadratic ▁equation ), ▁proport ions ▁( r ati os ), ▁and ▁the