3.1.1 Inserting half-twists

We can insert half-twists into a paper surface whenever a piece of the surface is homeomorphic to a rectangle ABCD with the following properties:

the edges AB and CD of the rectangle map to distinct parts of the boundary of the surface, and the edges BC and DA of the rectangle map to non-boundary points of the surface.

As illustrated in Author(s): The Open University

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In this performance video segment from From the Top at Carnegie Hall, Joshua Jones plays "Rhythm Song" on the marimba. Listen for the different rhythms in the piece. (04:29)
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In the Greek mythology, Sisyphus was a king who was cursed to roll a
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Except for third party materials and otherwise stated (see http://www.open.ac.uk/conditions terms and conditions), this content is made available under a http://creativecommons.org/licenses/by-nc-sa/2

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2 Sources of help

This assessment course is designed to be self-contained. However you might like to access the following sources for support and guidance if you need it. These sources include:

  • U529_1 Key skills – making a difference: This OpenLearn course is designed to complement the assessment courses. It provides detailed guidance and activities to help you work on your key skills, gives examples of key skills work from students, and helps you prepare and
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    Copyright © 2016 The Open University

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