Wannan fasaha an san shi da hanyar ƙarewa, kuma ya yi amfani da shi don kusan darajar π. A cikin ma'aunin da'irar ya yi wannan ta hanyar zana babban hexagon na yau da kullun a waje da ƙaramin hexagon na yau da kullun a cikin da'irar, kuma a hankali ya ninka adadin bangarorin kowane polygon na yau da kullun, yana lissafin tsawon kowane bangare na kowane polygon a kowane mataki. Yayin da adadin bangarorin ke ƙaruwa, yana samun kusancin kusan lambobi huɗu na zahiri. Bayan irin waɗannan matakan, lokacin da kowane bangare ya kasance mai daidaituwa, ya iya ba da amsoshi ga matsalolin zuwa daidaiton daidaito, yayin tantance iyakokin da amsar take. A cikin Measurement of a Circle ya yi wannan ta hanyar zana babban hexagon na yau da kullun a waje da kewaye da ƙaramin hexagon na yau da kullun a cikin da'irar, kuma a hankali ya ninka adadin bangarorin kowane polygon na yau da kullun, yana lissafin tsawon kowane bangare na kowane polygon a kowane mataki. Yayin da adadin bangarorin ke ƙaruwa, yana samun kusan kusancin
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