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Arkuski
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Suppose there is an ant at each of the four corners of a square with side length 1, such that (0,0) and (1,1) are at opposite corners of the square. The ant at (0,0) is facing the ant at (1,0) is facing the ant at (1,1) and so forth. Each ant will choose its path such that it is always facing the ant in front of it. If you can imagine this situation, the ants should all meet at the center of the square. Assume the ants are traveling at some constant velocity 1 as well.
This situation can be described as a system of differential equations. Each ant travels in a path that is identical to some rotation of the other paths. For example, the path that ant (1,0) takes is a 90 degree counter-clockwise rotation of the path that ant (0,0) takes. Therefore, if ant (0,0) travels on path [itex](x(t),y(t))[/itex], then ant (1,0) travels on path [itex](1-y(t),x(t))[/itex]. At any given point in time, ant (0,0) will be facing ant (1,0) such that [itex]\frac{y'(t)}{x'(t)}=\frac{x(t)-y(t)}{1-x(t)-y(t)}[/itex]. Let's go ahead and state the entire system as it applies to ant (0,0):
[itex]x'(t)^2+y'(t)^2=1[/itex]: Implies that velocity is constant
[itex]\frac{y'(t)}{x'(t)}=\frac{x(t)-y(t)}{1-x(t)-y(t)}[/itex]
[itex]x(0)=0[/itex]
[itex]y(0)=0[/itex]
[itex]x'(0)=1[/itex]
[itex]y'(0)=0[/itex]
If anyone knows how to attack a problem like this please share your insight!
This situation can be described as a system of differential equations. Each ant travels in a path that is identical to some rotation of the other paths. For example, the path that ant (1,0) takes is a 90 degree counter-clockwise rotation of the path that ant (0,0) takes. Therefore, if ant (0,0) travels on path [itex](x(t),y(t))[/itex], then ant (1,0) travels on path [itex](1-y(t),x(t))[/itex]. At any given point in time, ant (0,0) will be facing ant (1,0) such that [itex]\frac{y'(t)}{x'(t)}=\frac{x(t)-y(t)}{1-x(t)-y(t)}[/itex]. Let's go ahead and state the entire system as it applies to ant (0,0):
[itex]x'(t)^2+y'(t)^2=1[/itex]: Implies that velocity is constant
[itex]\frac{y'(t)}{x'(t)}=\frac{x(t)-y(t)}{1-x(t)-y(t)}[/itex]
[itex]x(0)=0[/itex]
[itex]y(0)=0[/itex]
[itex]x'(0)=1[/itex]
[itex]y'(0)=0[/itex]
If anyone knows how to attack a problem like this please share your insight!
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