Is the Closed Unit Square Homeomorphic to the Closed Unit Disc?

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metder
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I realize this is a classic problem, but I'm not sure exactly how to start on it:
Show that the closed unit square region is homeomorphic to the closed unit disc.
 
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metder said:
I realize this is a classic problem, but I'm not sure exactly how to start on it:
Show that the closed unit square region is homeomorphic to the closed unit disc.

Draw a picture and I think you will immediately see the mapping
 
I think Lavinia is suggesting you start by showing a single circle is homeomorphic to a single square, and then apply that to a family of expanding circles and squares filling up the regions.
 
mathwonk said:
I think Lavinia is suggesting you start by showing a single circle is homeomorphic to a single square, and then apply that to a family of expanding circles and squares filling up the regions.

yes. And I think this can be done with a simple function