PAL

Ptolemaeus Arabus et Latinus

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Paul of Gerresheim, Expositio practice tabule tabularum et propositionum Ptolomei pro compositione tabule sinuum et cordarum necessariarum

Brussels, BR, 1022-1047 · 196r

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erunt sinus arcuum etiam mediatorum, eo quod sinus est medietas linee cordantis duplum arcum. Unde si mediavero quantitatem corde arcus 16 graduum proveniet sinus arcus 8 graduum. Et in hoc terminantur considerationes compositionis tabule sinuum et cordarum. Sequitur nunc ipsa tabula rectificata anno domini 1443.