Why Is It Important to Understand Asymptotes in Math?

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Discussion Overview

The discussion revolves around the concept of asymptotes in mathematics, specifically addressing whether asymptotes intersect with curves or not. Participants explore definitions, interpretations, and examples related to asymptotes, including their behavior in relation to curves and tangents. The scope includes theoretical understanding and mathematical reasoning.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions whether an asymptote is a line that meets the curve, citing a definition that suggests it does not intersect.
  • Another participant clarifies that while curves may cross asymptotes at certain points, they do not touch them at the points where they are asymptotic.
  • A participant mentions that the term "tangent" is sometimes used in relation to asymptotes "at infinity," but emphasizes that this is merely an analogy.
  • One contributor describes an asymptote as a 'kiss' with the curve, indicating that the curve approaches the asymptote without ever touching it.
  • Another participant notes that the Greek origin of the term "asymptote" implies that a curve should never cross its asymptote, although they question the practical utility of this definition.
  • It is mentioned that a vertical or horizontal asymptote exists outside the domain or range of the graph, suggesting they do not intersect the graph.
  • However, a different viewpoint is presented, stating that a function can intersect its horizontal asymptote multiple times, providing the example of f(x) = sin(x)/x, which crosses the x-axis infinitely.

Areas of Agreement / Disagreement

Participants express differing views on whether asymptotes can intersect curves, with some asserting that they cannot while others provide examples of functions that do intersect their asymptotes. The discussion remains unresolved regarding the definitions and implications of asymptotes.

Contextual Notes

There are limitations in the definitions and interpretations of asymptotes, with some participants relying on specific mathematical contexts or examples that may not universally apply. The discussion reflects varying degrees of understanding and assumptions about the behavior of curves in relation to asymptotes.

pudasainigd
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Hey guys I am not being able to understand the Asymptote. Please say me wheather an Asymptote is a line that really meets the curve or not. If it meets its defination is not saying so beacuse its defination is like this "An asymptopte is a line whose perpendicular distance from any point on the curve tends to zero as the point goes to infinty". This defination is clearly suggesting that the line actually doesn't meet the curve. But while deriving the formula to find out the asymptopte of a curve we have solved the equations of a line(asymptopte) and of curve. How can we do it if it really doesn't meet the curve.
Still another thing; if the line meets the curve isn't it a tangent to that curve. Then the equation of asymptote will be same as that of tangent to that curve.
How can I undersatand this all? If you know any good websites that can provide me the detail infornmation about asymptote please mention it...
 
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pudasainigd said:
Hey guys I am not being able to understand the Asymptote. Please say me wheather an Asymptote is a line that really meets the curve or not. If it meets its defination is not saying so beacuse its defination is like this "An asymptopte is a line whose perpendicular distance from any point on the curve tends to zero as the point goes to infinty". This defination is clearly suggesting that the line actually doesn't meet the curve. But while deriving the formula to find out the asymptopte of a curve we have solved the equations of a line(asymptopte) and of curve. How can we do it if it really doesn't meet the curve.
I don't understand what you mean by "solved the equations of a line(asymptopte) and of curve" It might happen that the curve crosses it asymptote at some x value away from where ever the line is asymptotic to the curve but they do not touch at that x. I, certainly, have never seen an example of finding an asymptote by solving the equation of a line and curve simultaneously. Could you give an example of this.

It is sometimes said that an asymptote is "tangent" to a curve "at infinity" but, of course, that is only an analogy. There is no point "at infinity" actually on a curve.

Still another thing; if the line meets the curve isn't it a tangent to that curve. Then the equation of asymptote will be same as that of tangent to that curve.
Yes, a tangent to a curve meets the curve at the point of tangency. An asymptote does NOT and so is not a tangent.

How can I undersatand this all? If you know any good websites that can provide me the detail infornmation about asymptote please mention it...
Wikipedia is always a good place to start:
http://en.wikipedia.org/wiki/Asymptote
 
One of my mathematics professors described an asymptote as a 'kiss'. What the equation is actually stating is that the curve is forever pointed towards the axis, but will never touch it. It appears to cross the axis in some cases, be tangent in others, and can become indistinguishable from the axis as well.

It is helpful to think relatively by using different yard sticks to measure the distance of the asymptote from the axis. If you use a meter stick the asymptote may appear to touch the axis, however if you use a micrometer stick, it may appear as though it is going to touch if you keep following it.

If you follow it forever, you will find that the angle at which the curve is approaching the axis decreases with distance. It will never be tangent and it will never touch.

Tangent is when the lines are 'always' equal distance from each other, never converging, never diverging.
 
Well, due to the Greek origin of the word "asymptote" (non-touching), it is evidently technically correct to say that a curve should never, ever cross its asymptote.

However, one might ask if such a concept is a particularly useful distinguishing criterion.

Instead, the concept of a line that will, in the limit, have the same behaviour as the curve itself is a more general concept, and thus, presumably, more useful.
Several authors use "asymptote" for such a limiting line.

Note that in the latter case, the curve might well criss-cross the limiting line.
 
Last edited:
asymptotes simplified

It's a simple concept, Try graphing 1/x as x -> 0. We never touch to the y-axis (i.e. x =zero). It is an undefined infinity, an asymptote. .
IFF x were to = 0 then, there'd be no argument.
 
A vertical or horizontal asymptote does not intersect the graph as each one exists outside the domain or range.
 
Actually, you can have a function that intersects its horizontal asymptote an infinite number of times. Take f(x)= \frac{sinx}{x}. It has a horizontal asymptote at y=0 (provided that you use the the more liberal definition of asymptote aldrino gave), but also crosses the x-axis an infinite number of times.
 

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