Apollonius, of Perga · Venetiis : Apud Bernardum Iuntam · leaf 30
tur L G, cuizqualis pona tur BK, & iunda quoque KD ;zcetlatas BC, in I. Dicofpfam IK problema efhicere. lungantur enim LE,EH, HG. Quoniam igitur portio circuli EFG fufcipit anguluni zqua- . lé angulo C B K, angulus ELG zqualis €ipfi CBK. Et quoniani quadtilate- rum LEHG ettincircu- | lo,anguli EHG,… … fG infifteutes funt equa- les, ergo augalus DBC ángulo EHF equalis erít; fed angulo EHF , quadri- lateri EHFL,in circulo e- qualis eft angulus M L E, externus videlicet inter- no, & oppofito, ergo ani- gulus DBC equalis eft angu
Mathematics, Greek · Geometry -- Early works to 1800
Internet Archive · Fisher - University of Toronto · Public domain (published before 1931). Free to use for anything.
![An illustration from Sphaera mundi, seu, Cosmographia demonstratiua, ac facili methodo tradita : in qua totius mundi fabrica, vna cum nouis, Tychonis, Kepleri, Galilaei, aliorumq[ue] astronomorum adinuentis continetur : accessere, I. Breuis introductio ad geographiam. II. Apparatus ad mathematicarum studium. III. Echometria, idest geometrica tractatio de echo. IV. Nouum instrumentum ad horologia describenda, opus posthumum. (1635)](https://img.insideoutlibrary.com/img/200/ia-sphaeramundiseuc00bian-32-0.webp)
