{"book":"adl0946","page":274,"text":"۲۶۶\nخود شان با هم مساویند پس زاویه ج مساوی نصف زاویه مرکزی\nمقابلش یعنی ه می باشد -\n۳۰۱ - حال فرض می کنیم که زاویه محاطی مفروض در دو طرف\nقطری که از رأس زاویه گذشته است واقع شده باشد.\n(ش۲۱۴) از نقطه ج به مرکز ه\nوصل کرده امتداد میدهیم تا\nمحیط دائره را در نقطه ح قطع\nکند زاویه ا ح د مساوی با\nمجموع دو زاویه و ح ج و ج ح د\nو چون این دو مرتباً با نصف\nدو زاویه مرکزی ا ه ج و ح ه د مساوی می باشند پس زاویه\nا ح د که مجموع آنها است مساوی با نصف زاویه مرکزی ا ه د\nمی باشد -\nاگر دو ضلع زاویه در یک طرف قطری باشند که از رأس\nزاویه گذشته است (ش۲۱۵) مانند مطلب سابق اثبات می کنیم","chars":562,"image":"https://storage.googleapis.com/adl-page-images/adl0946/00274.jpg","first_page":1,"last_page":327,"title":"Handasah-ʼi musaṭṭaḥah barā-yi ṣinf-i haftum-i makātib-i rushdīyah, bi-qarār-i prūghram-i Vizārat-i Jalīlah-ʼi Muʻārif-i Afghānistān هندسۀ مسطحه :هندسۀ مسطحه","permalink":"https://afghanpress.org/book/adl0946/274","canvas":"https://afghanpress.org/iiif/adl0946/canvas/274","source":"https://afghanistandl.nyu.edu/books/adl0946/","source_pdf":"https://afghanistandl.nyu.edu/pdf/adl0946_download.pdf","rights":{"image":{"statement":"Public domain. NYU states: \"All works presented on this website are, unless otherwise indicated, in the public domain. The images available on this website may be freely reproduced, distributed and transmitted by anyone for any purpose, commercial or non-commercial.\"","uri":"http://rightsstatements.org/vocab/NoC-US/1.0/","holder":"New York University Libraries","source":"https://afghanistandl.nyu.edu/about.html","delivery":"Images are served from a copy mirrored by this project, not from NYU's servers, under the reproduction terms above.","endorsement":"This is an independent project. It is not affiliated with, endorsed by, or reviewed by New York University."},"text":{"statement":"Machine-generated transcription, dedicated to the public domain under CC0 1.0. No warranty of accuracy: see the provenance block on every page.","uri":"https://creativecommons.org/publicdomain/zero/1.0/","holder":"Steps Ventures"}},"provenance":{"text_produced_by":"gemini-3.1-pro-preview","thinking_level":"low","read_completed":"2026-08-09","per_page_confidence":null,"per_page_confidence_note":"Not recorded during the corpus run. No calibrated per-page score exists, and none is estimated here.","human_reviewed":false,"accuracy_context":"Roughly two thirds of characters agree with a modern printed edition of the same text. Much of the disagreement is editorial, not misreading. Treat the transcription as a finding aid and read the page image before quoting.","primary_source":"The page image. The text is an index into it."}}