Week 5: Circular Logic

A shape is formed as follows:

A circle is drawn such that the points A, B, C, D are equally spaced around the circumference.  The arcs AB and CD are reflected in the lines AB and CD respectively.

This makes the following shape:

Screen Shot 2022-12-07 at 3.38.58 PM

(a)       Find the area of the shaded shape when the radius, r, of the original circle is 1.

(b)       What is the area of the shaded shape when r = a?

Teacher notes:

Level of difficulty:  Accessible for SL and HL students

Syllabus knowledge required:  Sectors and segments

This would be a good starter which can be done as a non-calculator exercise.  


You can download a pdf of the solution here.

Published by Ibmathsresources.com

Maths teacher

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