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التشبيه المحتمل هو ذلك مع العشروني المبتور(Truncated icosahedron). علما بأن العشروني المقطوع هو متعدد وجوه مكون من 32 شكلا: 20 سداسي و 12 خماسي.
Clathrus ruber |
العشروني المبتور |
Clathrus ruber |
العشروني المبتور |
تقريب هندسي متعدد الوجوه لسطح اهليجي في وضع عام حيث محور التحول متماس للسطح نفسه Approssimazione poliedrica di un ellissoide generica k con l'asse di generazione tangente k |
the case in which the generation axis of a quadric is tangent to it الحالة التي يكون فيها محور تحول رواسم سطح ثنائي k متماس للسطح نفسه |
المستوى المتماس لسطح اهليجي k عند نقطة لا تنتمي لأي مستوى محوري للسطح نفسه the tangent plane to a quadric k at a point not belonging to any axial plane of k |
مركزي الارتداد بين مخروطيتين غير متشابهتينThe centers of involutions between two generic conics. i centri di involuzioni tra due conichegeneriche |
Conditions for obtaining the same ellipse as an image of a circle شروط الحصول على نفس القطع الناقص كمنظور لدائرة |
قياس الزاوية المركزية المقابلة لقوس دائري يساوي ضعف قياس الزاوية المحيطية المقابلة للقوس نفسه. |
"المنظور الصلب" (Solid perspective) هو أداة متعددة الاستخدامات ليس فقط لانشاء الوهم المادي للابعاد المكانية، بل يقدم طريقة مرنة لنمذجة وتصميم فراغات مثيرة للاهتمام. |
تقابل على سطح مخروطي |
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the works of the student Maram Tarawneh |
To achieve this, it is important to teach descriptive geometry in a gradual manner, starting with the basic concepts and gradually progressing to more complex concepts. This can help students understand the concepts better and apply them more effectively.
It is also important for students to solve many different problems in descriptive geometry. This can help students develop their understanding of the subject and apply it effectively.
The teacher should provide students with all the data, suggestions, analyses, illustrations, and practical solutions necessary to solve various engineering problems. This can help students understand the concepts better and apply them more effectively.
It is also important to pose many additional problems for students. These problems can help students develop their creativity and apply geometric concepts in different ways.
Dr. Hasan ISAWI
https://isawi.blogspot.com/2024/01/13-14.html15 |
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خط باسكال | . |
Pascal line |
Given five points (R,R′,A,B,C) of an ellipse, we want to determine a sufficient number of points to draw it.
Procedure
Summary
Translation
Costruzione di un'ellisse, dati 5 punti
Dati cinque punti (R,R′,A,B,C) di un'ellisse, si vuole determinare un numero sufficiente di punti per disegnarla.
Procedura
Riepilogo
Construction of an Ellipse, given 5 points
Given 5 points (R, R', A, B, C). of an ellipse, we want to determine a sufficient number of points to draw it.
Procedure
Choose two points as projection centers, from them draw the projection lines a-a', b-b', c-c' (points common to corresponding lines are the points of the conic).
Points common to non-corresponding lines are aligned with the center of the projectivity.
Find the point of intersection between the two lines a', b' Find the point of intersection between a, b' Connect the intersection points E, F thus identifying a line suitable for identifying the center of the projectivity
Dati 5 punti (R, R', A, B, C).di un ellisse, si vuole determinare un numero sufficiente di punti per disegnarla.
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Punti comuni a rette non corrispondenti sono allineati con il centro della proiettività. Si trova il punto d'intersezione tra le due rette a', b |
Si trova il punto d'intersezione tra a, b' |
Si uniscono i punti d'intersezione E, F individuando cosi una retta atta ad individuare il centro della proiettività |
Si trova il punto d'intersezione tra b', c |
Si trova il punto d'intersezione tra le rette c', b (esterno rispetto al foglio) e si unisce con il punto G |
Si trova il punto d'intersezione tra le rette a', c |
Si trova il punto d'intersezione tra le rette a, c' (esterno rispetto al foglio) e si unisce con il punto H |
si vuole individuare un altro puto dell'ellisse e perciò si traccia, in modo arbitrario, la retta d' |
si opera il prodotto in croce per individuare la retta d, con la procedura seguente: 1 - Le rette d', c si incontrano nel punto I |
2- si proietta il punto I dal centro della proiettivita U individuando il punto L sulla retta C' |
2- si proietta il punto L dal centro R individuando la retta d |
l'incontro tra le rette corrispondenti d, d' individua un altro punto dell'ellisse. |
con la stessa procedura, eseguita in precedenza, si possono trovare altri punti per disegnare l'ellisse |
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