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Question 9.18 on Geometry II-A

 
 
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Question 9.18 on Geometry II-A
by Jimmy Muren - Wednesday, November 8, 2017, 8:15 PM
 

In the 2x2x2 cubic figure below, if the path is required to be along the surface of the cube, what is the length of the shortest path from point A to point B?

I found that the shortest path along the surface would be to go from A to the opposite vertex of the square and then straight to B, but the answer I got was 2+sqrt(2) and I don't think the HW submission thing will accept that kind of answer. Did I do something wrong?

 
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Re: Question 9.18 on Geometry II-A
by Areteem Professor - Friday, November 10, 2017, 5:21 PM
 

Thanks for pointing this out. The wording of the problem has been updated to say the answer can be written in the form $\sqrt{K}$ for an integer $K$.

However, this still doesn't match your answer of $2 + \sqrt{2}$, so you can use this as a hint that you can actually get a shorter distance.

Let us know if you have any other questions.