# De utilitate mathematicae 208

Theon Smyrnaeus, De utilitate mathematicae, Paragraph 208. Ancient Greek.

Canonical: https://interlinea.aeterna-institute.org/library/greek/theon-smyrnaeus/de-utilitate-mathematicae/208

ἐὰν δὲ ἀνάπαλιν τὸ μὲν φωτίζον μεῖζον, καθά- περ τὸ ξο, τὸ δὲ φωτιζόμενον 〈ἔλαττον〉, οἷον τὸ πρ, σφαιρικὰ δὲ ἄμφω, δῆλον ὅτι ἡ τοῦ πρ σκιά, τουτέστιν ἡ πρσ, κωνοειδὴς καὶ πεπερασμένη γενήσεται, τῶν ξπ ορ ἀκτίνων ἐπʼ εὐθείας ἐκβαλλομένων καὶ συμπιπτου- σῶν ἀλλήλαις κατὰ τὸ σ σημεῖον, ἐπειδὴ ἐλάττων ἐστὶν ἡ πρ διάμετρος τῆς ξο, καὶ τούτου γινομένου πανταχόθεν.

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Theon Smyrnaeus, De utilitate mathematicae, ed. Eduardus Hiller. Text: The Greek Library, from the Perseus Digital Library and other open sources, CC BY-SA 4.0. Changes: apostrophes normalised and the text divided into reading sections by Interlinea.
License: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Source: https://thegreeklibrary.pages.lisn.upsaclay.fr/works/tlg1724.tlg001.local001/.