# Optica μη΄.

Euclid, Optica, μη΄.. Ancient Greek.

Canonical: https://interlinea.aeterna-institute.org/library/greek/euclid/optica/%CE%BC%CE%B7%CE%84.

Εὑρεῖν τόπους, ἀφʼ ὧν τὸ ἴσον μέγεθος ἥμισυ φανεῖται ἢ τέταρτον μέρος ἢ καθόλου ἐν τῷ λόγῳ, ἐν ᾧ καὶ ἡ γωνία τέμνεται. ἔστω ἴσον τὸ ΑΖ τῷ ΒΓ, καὶ περὶ τὴν ΑΖ γεγράφθω ἡμικύκλιον, καὶ γεγράφθω ἐν αὐτῷ ὀρθὴ γωνία ἡ Κ· τῇ δὲ ΑΖ ἴση ἔστω ἡ ΒΓ, καὶ περὶ τὴν ΒΓ περιγεγράφθω τμῆμα, ὃ δέξεται τῆς πρὸς τῷ Κ γωνίας ἡμίσειαν. οὐκοῦν ἡ Κ γωνία διπλασία ἐστὶ τῆς ∠ γωνίας. διπλασία ἄρα φαίνεται ἡ ΑΖ τῆς ΒΓ τῶν ὀμμάτων ἐπὶ τῶν ΑΚΖ, Β∠Γ περιφερειῶν κειμένων.

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Euclid, Optica, ed. Johan Ludvig Heiberg, Heinrich Menge. 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/tlg1799.tlg009.local001/.