Can you Call this a standard limit?

In summary, the conversation is about the discovery of a limit, lim x->0 sin(nx)/x = n, which the person claims to have invented. However, others point out that this limit is well known and can be easily derived from the standard limit, lim x->0 sin(x)/x = 1. They also mention that this limit has appeared in various calculus textbooks and therefore cannot be claimed as a new discovery. The conversation ends with a suggestion to be open-minded about new discoveries and not become too focused on existing solutions.
  • #1
ZeroPivot
55
0
lim x->o sin(nx)/x = n for n E real numbers

i haven't seen it in any books but it works.
 
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  • #2
If we put ##y = nx##, then the limit is equivalent to
$$\lim_{y \rightarrow 0} \left( \frac{\sin(y)}{y/n}\right) = \lim_{y \rightarrow 0}\left( n \frac{\sin(y)}{y}\right) = n \left(\lim_{y \rightarrow 0} \frac{\sin(y)}{y}\right)$$
The limit inside the parentheses on the right hand side is standard, equal to ##1##. (Proof?)
 
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  • #3
ZeroPivot said:
lim x->o sin(nx)/x = n for n E real numbers

i haven't seen it in any books but it works.
It can be derived from this limit:
$$\lim_{x \to 0}\frac {sin(x)}{x} = 1$$

$$\lim_{x \to 0}\frac{sin(nx)}{x} = \lim_{x \to 0}\frac{n \cdot sin(nx)}{nx} $$
$$= n \lim_{u \to 0}\frac{sin(u)}{u} = n\cdot 1$$
 
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  • #4
so I am a genuise right for inventing it?
 
  • #5
ZeroPivot said:
so I am a genuise right for inventing it?
Usually, potential candidates for the Fields Medal must wait to see if it is awarded to them. :smile:
 
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  • #6
ZeroPivot said:
so I am a genuise right for inventing it?
I've seen this problem in several calculus books, so I think you're premature in saying that you invented it.
 
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  • #7
Mark44 said:
I've seen this problem in several calculus books, so I think you're premature in saying that you invented it.

problem yes, but general standard solution no. they just say lim x->o sint/t = 1
my way is far more efficient.
 
  • #8
Since it has appeared as a problem in many textbooks, thousands upon thousands of students have worked it, so you can't say you invented something that many people have done before you thought of doing it.
 
  • #9
Mark44 said:
Since it has appeared as a problem in many textbooks, thousands upon thousands of students have worked it, so you can't say you invented something that many people have done before you thought of doing it.

many people have done many things but since i have not seen anywhere

lim x->o sin(nx)/x = n

you can say that I invented it. its like you know dancing many people could have foxtrotted but its the person that calls it foxtrot and creates a perimeter of foxtrot he/she is the inventor.

The GREAT thing about my standard limit is that its FAR superior to the wellknown standard limit that is lim x->0 sinx/x = 1 this is far inferior to my limit.
 
  • #10
It is not "your" limit. It is a completely trivial corollary.
 
  • #11
arildno said:
It is not "your" limit. It is a completely trivial corollary.

show me where lim x->0 sin(nx)/x = n is written?

i feel a lot of hostility here i don't know why, i thought this forum was about comradery and discussing ideas about science without persecution.
 
  • #12
Zero, just because you write something down which has not been literally word for word written down doesn't mean it is a great discovery that you have made. Anybody who has a solid understanding of calculus would have been able to calculate your limit immediately upon seeing it.

Furthermore, not that it's terribly relevant, but your result is stated in this here yahoo answer:
http://answers.yahoo.com/question/index?qid=20090919181027AADfJkR
lim x->0 sin(nx)/nx = 1

A genuine mathematical discovery is when you can answer a problem that people have been unable to answer before; answering a problem that people simply haven't bothered to write down before isn't a discovery, it's just applying some math to a problem.
 
  • #13
We are disputing your claim that you "discovered" something that has appeared in print for many years. I don't have any calculus textbooks with me right now, but I'll bet you could find this in many of the books that are used in calculus courses, such as Thomas-Finney, Larson, and others.
 
  • #14
Ok we have a lot of haters here today.

All I am saying is that the standard limit: lim x->0 sin(nx)/x = n is FAAAAAAR superior than lim x->0 sin(x)/x = 1
its not trivial at all. the yahoo link provided above is not my Standard Limit and its not as simple and elegant.

I think people here should be more open minded about discoveries you know a lot of scientist work so far they become nearsighted to great solutions and things do slip the system.
 
  • #15
ZeroPivot said:
Ok we have a lot of haters here today.
You are confused if you think what has transpired here falls under the category of "hate." No one has said anything of a personal nature about you. We have made valid points that contradict your claim of inventing something.
ZeroPivot said:
All I am saying is that the standard limit: lim x->0 sin(nx)/x = n is FAAAAAAR superior than lim x->0 sin(x)/x = 1
its not trivial at all. the yahoo link provided above is not my Standard Limit and its not as simple and elegant.
As already stated, "your" limit is well known, and is an easy corollary of the sin(x)/x limit.
ZeroPivot said:
I think people here should be more open minded about discoveries you know a lot of scientist work so far they become nearsighted to great solutions and things do slip the system.

Since you don't have any more to offer, I am closing this thread.
 

1. What is a standard limit?

A standard limit is a predetermined value or threshold that is used as a reference point for comparison or evaluation. It is often used in scientific studies and experiments to determine whether a certain condition or result is considered to be within a normal range.

2. How is a standard limit determined?

A standard limit is typically determined through extensive research and data analysis. Scientists may conduct numerous experiments and collect data from various sources to determine a range of values that can be considered normal or standard.

3. Why is it important to have a standard limit?

Having a standard limit allows for consistency and accuracy in scientific research. It provides a benchmark for comparison and helps to identify any outliers or abnormalities in data. It also allows for easier interpretation and communication of results.

4. Can a standard limit change over time?

Yes, a standard limit can change over time as new research and data becomes available. It is important for scientists to regularly review and update standard limits to ensure they are still relevant and accurate.

5. Is there a universal standard limit for all experiments and studies?

No, there is not a universal standard limit for all experiments and studies. Standard limits may vary depending on the specific field of study, the type of data being analyzed, and other factors. It is important for scientists to establish appropriate standard limits for their specific research.

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