Originally posted by: Leros
(assuming the lines are randomly distributed) A plane with infinite lines is a plane where: for every x and y there exists a point (x,y).
In other words, the plane is completely filled in.
False. Consider the standard x-y plane. I place a line at every positive value of x, i.e. my lines are x=1, x=2, x=3, etc. Now I have an infinite number of lines but the plane is not at all filled in.
The key here is the difference between countable & uncountable infinity.
Originally posted by: episodic
If you had a plane figure which was a polygon which had an infinite number of sides - would that be a circle?
Technically, no. First, as argued by
destrekor, a circle has no sides; it is not a polygon. But then again, a polygon cannot have an infinite number of sides, b/c it would cease to be a polygon.
Secondly, you'd have to be working with a regular polygon. If I created an irregular, concave polygon, then that most certainly would not look like a circle, ever.
But I'm sure we all understand the spirit of what you're asking. If you consider a sequence of regular polygons (whose vertices are equidistant from a point) with more and more edges, the area and perimeter will, in the limit, approach that of a circle.