MHB Greatest Common Divisor: Applications in Tiling and Number Theory

AI Thread Summary
The greatest common divisor (GCD) has significant applications in number theory and practical scenarios like tiling. For a rectangle with integer dimensions, the largest square that can tile it perfectly has a side length equal to the GCD of its width and height. This principle ensures that tiles fit correctly without needing adjustments, which is crucial for aesthetic and functional purposes in flooring. While the GCD is a fundamental mathematical concept, its direct applications may not be extensive beyond basic tiling and number theory. Overall, the GCD serves as a foundational tool in various mathematical and real-life contexts.
matqkks
Messages
280
Reaction score
5
Are there any real life applications of greates common divisor of two or more integers?
 
Mathematics news on Phys.org
Absolutely. It is used basically everywhere in number theory, and, therefore, in all applications of number theory. If you mean applications depending only and directly on the greatest common divisor, then, for instance:

If you have a rectangle of dimensions $\text{W} \times \text{H}$ metres - integer dimensions, obviously - then the largest square that can tile the rectangle perfectly has side length $\gcd \left ( \text{W}, \text{H} \right )$.

This has - on some level - applications in everyday tiling: if you want your tiling to correctly fit the floor, you want to make sure you meet the condition above, else it will look odd as the edge tilings won't fit and will need to be cut down. This depends on the dimensions of the floor that is to be tiled. The same reasoning can be applied to more complex tilings (which are often compositions of simple tilings of various shapes) to make sure they all fit together and repeat nicely.

That said, if you are looking for more concrete, "serious" applications, I'm not sure you'll find any to your liking. The greatest common divisor isn't a particularly broad concept but rather a mathematical building block, and your question would then be akin to "what are real life direct applications of addition" which I am sure you can agree is difficult to answer (the best answer being, ultimately, "everything, on some level").​
 
Seemingly by some mathematical coincidence, a hexagon of sides 2,2,7,7, 11, and 11 can be inscribed in a circle of radius 7. The other day I saw a math problem on line, which they said came from a Polish Olympiad, where you compute the length x of the 3rd side which is the same as the radius, so that the sides of length 2,x, and 11 are inscribed on the arc of a semi-circle. The law of cosines applied twice gives the answer for x of exactly 7, but the arithmetic is so complex that the...
Just chatting with my son about Maths and he casually mentioned that 0 would be the midpoint of the number line from -inf to +inf. I wondered whether it wouldn’t be more accurate to say there is no single midpoint. Couldn’t you make an argument that any real number is exactly halfway between -inf and +inf?
Back
Top