{"book":"adl0946","page":276,"text":"۲۶۹\nوصل میشود مساوی با نصف وتر است.\nاثبات عکس این مطلب اخیر را بعهده متعلمین واگذار میکنیم\n۳۰۳ - از قضیه ۳۰۱ معلوم می شود که هر گاه چندین زاویه\nیک قوس از دائره جدا کنند یا یک دیگر مساویند مثلاً دو زاویهٔ\nا ج د و ا ل د با هم مساویند زیرا که هر دو یک قوس ا د را\nاز دائره جدا می کنند (س۲۱۷)\nبنا بر این هر گاه نقطه ج یعنی\nراس زاویه تغییر کند مقدار زاویهٔ\nتغییر نمی کند بشرط آنکه دو نقطه\nا و د ثابت باشند.\n۳۰۴ - زاویهٔ محاطی مخصوصه\nزاویهٔ ا ج د را ملاحظه میکنیم (س۲۱۸) که یک ضلع آن ا ج وتر دائره و\nضلع دیگر ج د مماس بر دائره است زاویه ا ج د محاطی مخصوصی است که\nقوس مقابلش ا ج است که در درون زاویه واقع شده است اگر ضلع ا ج\nقطر دائره باشد زاویه ا ج د قائمه خواهد بود (س۲۱۹) و در اینجا هم معلوم","chars":686,"image":"https://storage.googleapis.com/adl-page-images/adl0946/00276.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/adl0946/276","canvas":"https://afghanpress.org/iiif/adl0946/canvas/276","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."}}