Posts

Showing posts from January 10, 2019

Question on convex pentagons with lattice points as its vertices

Image
1 I have the following question which I found as an example in a book with me: "All vertices of a convex pentagon are lattice points, and its sides have integral length. Show that its perimeter is even" The book starts the solution like this: "Colour the lattices as in a chess board and erect right triangles on the sides of the pentagon with the sides of the pentagon as the longest side. With the other two sides along the sides of the square trace the ten shorter sides. Since at the end we return to the point we started we must have traced an even number of lattice points." How is the last statement concluded? graph-theory share | cite | improve this question ...

USB stick not in /dev

Image
2 1 I'm new on this community, newcomer to the Arch distribution, and I hope to post in the good section :) I think it's a Hardware problem rather than a distribution problem. I am currently trying several Arch distributions before permanently installing a basic Archlinux. To do this, I create a bootable USB key from downloaded ISOs (after checking the SHA1 and MD5). By reinitializing and formatting the USB key, I think that there was a failure when writing on the key. Now the USB is not available in /dev/sdb Story First, I created a bootable key and installed Arcolinux on my machine. Then I decided to do the same for Antergos from current Arcolinux. When reinstalling the USB key: the writing of the ISO worked, then I rebooted the machine to boot on the key, but the machine did not succeed. Indeed, loo...