Hyperreal Intermediate Value Theorem

In summary, the conversation is about the transfer of the intermediate value theorem in Elementary Calculus: An Infinitesimal Approach by Jerome Keisler. The question is whether a continuous function defined on the hyperreals will have a solution for any value within a "closed" interval. The star transform of the interval may not provide unlimited elements, so Los's theorem may not be applicable.
  • #1
poissonspot
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I haven't thought too much about this, but it seems to me that the intermediate value theorem would transfer. Am I incorrect?
 
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  • #2
conscipost said:
I haven't thought too much about this, but it seems to me that the intermediate value theorem would transfer. Am I incorrect?

In Elementary Caculus: An Infinitesimal Approach by Jerome Keisler in chapter 3, there is good proof of this.
The chapters and whole book is a free down-load HERE.
 
  • #3
Plato said:
In Elementary Caculus: An Infinitesimal Approach by Jerome Keisler in chapter 3, there is good proof of this.
The chapters and whole book is a free down-load HERE.

This was not quite what I was thinking about. But I think it helps clarify the question I had. I have not thought much about the topology of the hyperreals but what I'm asking is:

Say I have a continuous function defined on the hyperreals and I take a "closed" interval [a,b], that is the set of all hyperreals between a and b, where a and b may very well be unlimited, does it follow that for any c: f(a)<c<f(b) there exists an x so that f(x)=c.

The star transform of [a,b] wouldn't give unlimited elements as far I'm looking into it, so I'm afraid this would have to be proven using something other than Los's theorem.
 

FAQ: Hyperreal Intermediate Value Theorem

What is the Hyperreal Intermediate Value Theorem?

The Hyperreal Intermediate Value Theorem is a mathematical theorem that states that if a function is continuous on an interval, then it must take on every value between the endpoints of that interval. It is a more generalized version of the Intermediate Value Theorem, allowing for infinitesimal and infinite values.

How is the Hyperreal Intermediate Value Theorem different from the Intermediate Value Theorem?

The Hyperreal Intermediate Value Theorem differs from the Intermediate Value Theorem in that it allows for infinitesimal and infinite values, while the Intermediate Value Theorem only applies to real numbers. This allows the Hyperreal Intermediate Value Theorem to be applied to a wider range of functions.

Can the Hyperreal Intermediate Value Theorem be used to prove the existence of solutions to equations?

Yes, the Hyperreal Intermediate Value Theorem can be used to prove the existence of solutions to equations. This is because it guarantees that a function will take on every value between the endpoints of an interval, so if a function is continuous, then there must be a point where the function takes on the desired value.

Is the Hyperreal Intermediate Value Theorem a commonly used theorem in mathematics?

It depends on the field of mathematics being studied. The Hyperreal Intermediate Value Theorem is more commonly used in fields such as non-standard analysis, where infinitesimal and infinite values are considered. In other fields, the Intermediate Value Theorem may be more commonly used.

Are there any real-world applications of the Hyperreal Intermediate Value Theorem?

Yes, there are real-world applications of the Hyperreal Intermediate Value Theorem. It can be used in physics and engineering to prove the existence of solutions to equations, as well as in economics and finance to analyze continuous functions. It can also be applied in computer science and programming for numerical analysis and error analysis.

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