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Circle Angles

Circle Angles

Barrie Galpin


Schlagwörter Angles, Circle theorems

Seven activities in which students investigate angles in circles using basic geometric constructions.

Students start with a new, blank TI-Nspire document and, using a worksheet for guidance, work through the necessary constructions. The seven investigations are:

· Triangle on a Chord and Centre

· Perpendicular Bisector of Chords

· Inscribed Angle Theorem

· Angle in a Semicircle

· Tangent to a Circle

· The Tangent Kite

· The Cyclic Quadrilateral

In each case students are able to move points and see how the measurements of angles change. This will convince them that a particular result always seems to be true. They are then encouraged to prove the result, either using an algebraical or a geometrical approach.