How does multiplying infinity by 0 result in -1?

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Discussion Overview

The discussion revolves around the mathematical expression "infinity * 0 = -1" and its implications within the context of analytic geometry, particularly concerning the tangent function and the relationship between slopes of perpendicular lines. Participants explore the validity of the claim and the definitions involved.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant asserts that "infinity * 0 = -1" based on the relationship m1 * m2 = -1 for tangent values.
  • Another participant challenges the validity of the initial claim, questioning the assumptions made about the tangent function and its behavior at certain angles.
  • Concerns are raised about the definition of tangent at 90 degrees, with one participant arguing that it is not defined and thus cannot be evaluated.
  • Several participants express frustration over the lack of clarity in the original question and the need for precise definitions of terms used in the discussion.
  • There is a suggestion that the misunderstanding may stem from the informal use of mathematical symbols without proper context.
  • One participant emphasizes the importance of clearly explaining one's assumptions and definitions when posing mathematical questions.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the validity of the original claim. Multiple competing views remain regarding the interpretation of the tangent function and the assumptions underlying the mathematical expressions discussed.

Contextual Notes

Limitations include the unclear definitions of terms like "m" and the assumptions made about the behavior of tangent at specific angles. The discussion reflects a need for more rigorous definitions and clarity in mathematical communication.

ExecNight
infinity*0 = -1 ?

From Analitic Geometry;

Tan(x) = m

m1*m2 = -1


Tan(0) * Tan (90) = -1

Therefore;

0 * infinity = -1

What is wrong here?
 
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you mean apart from the fact it's rubbish?

what are m1 and m2? who says that they must satisfy that relation for *all* m1 and m2? they need not and they do not, even if I seconf gues what you mean, in fact this exact nonquestion has been asked beofer in this forum at least twice in the last couple of months. Why?
 
Matt,

How are you a "Math Guru" if you have no idea what is "tan(x) = m"

in Analitic Geometry?

Let alone you don't even know the Formula (m1*m2=-1) in that regard.
 
Yeah and:
tan(0)*tan(-90)=-1
→ 0*-[itex]\infty[/itex]=-1
→ 0*[itex]\infty[/itex]=1
The problem is assuming that tan(90) is infinity. It isn't. It's sin(90)/cos(90)=1/0 which doesn't have any meaning

edit:Matt knows m1m2=-1 for perpendicular lines, it just wasn't clear to him what m1 and m2 were in your post since you didn't say.
 
Last edited:
ExecNight said:
Matt,

How are you a "Math Guru" if you have no idea what is "tan(x) = m"

in Analitic Geometry?

Let alone you don't even know the Formula (m1*m2=-1) in that regard.
:smile:
This is just so silly..
BTW, the tangens function is not defined at 90 degrees, so you can't evaluate it there.
 
Oh well, i need to rewrite all the history behind an equation while asking a question?
 
ExecNight said:
Oh well, i need to rewrite all the history behind an equation while asking a question?
You must tell us what YOU mean by the terms you happen to use.
 
ExecNight said:
Oh well, i need to rewrite all the history behind an equation while asking a question?

Yes, since you happen not to know it!
 
Ok make a list here to me;

- How many different m= tan(x) are used in "Analitic Geometry", where m1*m2=-1 ?


Or do you think you are so "genius" when you come up with an idea that "m" might be any given number? So my question is an assumption on something i invented, so i should explain it to you... LOL
 
  • #10
First of all, the geometry you're talking about is neither syphilitic or analitic, it is "analytic".
You must define the (non-elementary) symbols you use, period. If you are unwilling to do so, kindly f**k off.
 
Last edited:
  • #11
ExecNight said:
Matt,

How are you a "Math Guru" if you have no idea what is "tan(x) = m"

in Analitic Geometry?

Let alone you don't even know the Formula (m1*m2=-1) in that regard.
Ahh yes, tan(x) = m immediately clarifies what m1 and m2 are...

If you are stuck on something and need our help, could you please clearly explain what it is.
 
  • #12
ExecNight: you have until your next post to tone down the attitude.

Did you ever stop to think that maybe, just maybe, we know what we're doing?

Did you ever stop to think that when someone asks you a question, it might not be because they want to hear the answer, but because they want you to hear the answer?

Did you ever stop to think that "what is wrong" might be hidden by your own sloppiness, and that by going over all the steps in full detail, your mistake would be utterly obvious?
 
  • #13
Yes, in most cases when a person writes m=tan(x), he is probably most often talking about the slope of a line, and then when you see m1m2=-1 after that, it probably makes most people think of perpendicular lines, but its possible that they are talking about something else. If you read matt grime's post you see that he understood what you probably meant, but just didn't reject the possiblity that you meant something else, that's all.
 
  • #14
Attack deleted. Thread closed.
 

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