The diagram shows a square with edges of length 1, and four arcs, each of which is a quarter of a circle. Arc has centre ; arc has centre ; arc has centre ; and arc has centre .
What is the length of the perimeter of the shaded region?
Input note: give your answer as an exact value in terms of .
Select one option, then click Submit.
6
(2\sqrt{2} - 1)\pi
(\sqrt{2} - \frac{1}{2})\pi
2\pi
(3\sqrt{2} - 2)\pi
Select an option, then submit.
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