Infinity Definition and 988 Threads

Hello everyone I'm confused...i was just doing RL and RC circuits without a driven source, they made sense after doing them a few 100 times. Now I'm at Driven RL circuits. My professor said: iL(infinity) = 2mA iL(0+) = 0. From my understanding, i thought at infinity, the switch has been...

We defined the definition of a closed set to be: "F\subset\mathbb{R} is closed if the limit of any convergent sequence in F is an element of F." Now we have also defined that a sequence may "converge to infinity". Is infinity considered a point in N?

I was wondering if it would be possible to find the average value of a function with the only condition that x is element of R. For example, could we say that f(x)=4 has an average value of 4 since no matter what values we give for a or b in the integral from a to b of f(x)/(b-a) (b is not equal...

Working on pervect's "messy unsolved" problem has led me to an interesting result. Let \left( x , t \right) be a global inertial coordinate system for Minkowski spacetime. Consider the worldline given by t \left( \tau \right) = \frac{\tau^3}{3} - \frac{1}{4 \tau} x \left( \tau \right) =...

may i know (cos n pi ) with n to infinity is converges or diverges?? may i know (cos n pi ) with n to infinity is converges or diverges??

may i know is it lim x to 0 (1/sinx - 1/x ) is equals to infinity??

Hello I was watching lectures on Quantum Computing another day and I came up with a problem. I talked to my school teachers about it but everyone seemed to dodge my question except for one, my math team teacher who told me that without assuming anything it cannot be solved. Or we can take the...

Hi, What is the limit of ln(\frac{1+1/ \sqrt(1+1/R)}{1-1/ \sqrt(1+1/R}) as R reaches infinity. (latex did not show it very well. But the numerator is same as denominator except there is a + sign instead of a - sign. As R reaches infinity the argument of the ln reaches...

i think maybe this question was posted in this furoms for so many times but i want to ask it again in my own version.. d' question goes like ths.. is there such thing as infinity? i mean for example, infinite time or infinite quantity of space or matter? if so, then how could it be...

I have an interest in physics, I have not studied it at any high levels (as u will soon find out :smile: ), i just like to read and think about it, but I have a question, please don't blind me with maths! If a singularity at a black hole has infinity density, I'm guessing this means it has...

let,s suppose that we have the limit with n tending to infinity: \frac{f(n)}{g(n)}=1 then i suppose that for n tending to infinity we should get: f(n)\rightarrow{g(n)} or what is the same the function f(n) diverges as g(n) as an special case: \pi(n)\rightarrow{n/ln(n)} where Pi is the...

of doing this \lim_{x\rightarrow +\infty }\cos^{x}\frac{\pi}{x} than using \cos x \simeq 1- \frac{x^{2}}{2} \mbox {when "x" goes to zero} ? Daniel.

Hello Everyone, I'm doing some practice problems and I am stuck on the following limits. 1) Limit as x approaches infinity of (sin^2(x))/x^2 Now for this one I thought that the answer would just be 1 seeing as the limit of sinx/x is 1, however the answer is apparently 0 and I can't see the...

I heard about this debate and wanted to share with you what information I have gathered so far...maybe you'all can find more out about it. I'll try and keep you posted, and thought maybe this would be a great subject to keep posted on!? For now though, I just wanted to let you know about it...

Hey, I recenty took an exam and the professor asked us to turn in a corrected version of the exam based on the comments he made to us (I guess people didn't do as well as he expected). On one of the problems it asks: How much work does it take for you to move a charge Q from infinity to the...

are the input impedances for both inverting and non-inverting amplifiers infinity?

Is the summation of k = 1 to infinity for n2k equal to n2 / (1 - n2)?

Hi, Here is the question: Prove that if the sequence {s} has no convergent subsequence then {|s|} diverges to infinity. To me, this seems so easy, but I'm having a really hard time putting it down in a rigorous manner. My thoughts are: every convergent sequence has a convergent...

I`m relativly new to Physics but have heard of a technic used called renomalisation, the cancelling of infinties. If infinity is not a number how does this work? (my appologies to the mods if i`ve posted this in the wrong place)

Hello there, please tell me whether e^{iS} = 0 when S = +\infty S is the action of a particle = \int L dt e.g. when the particle goes to infinity and comes back, kinetic energy blows up, then S blows up.

I can sort of deal with it conceptually, and even work with it mathematically - but are there any examples of it as a property of something in the physical universe? (I'm probably missing something obvious..)

I gave roughly an hour's thought to infinity, and came up with these statements and questions; If infinity exists, where would it go? The only infinity that would make sense is the size of the universe, because you couldn't have an infinite amount of any matter without it taking up literally...

Is it correct that \[ \Re ^\infty = \left\{ {\xi \in \Re ^N \left| {\exists n \in N:\forall k > n\,\xi _k = 0} \right.} \right\} \] , N denoting the natural numbers? If not, is there another symbol for the left hand side of the equation? Is this also used with any other set containing a...

With the real number line. 0 is before -1 and 1. Both zero, and infinity are undefined. How does 0 touch infinity. Both are the same value, and start at 0, so for there to be infinity either infinity starts from infinity, or infinity starts from 0. In fact infinity has both values. It...

Is infinity - 1 still infinity. Also if 1\3 = .333... then wouldent 3\3not only = 1 but .999... as well?

Zero x infinity = -1 ?! when two lines meet perpendicularly, we hv the formula v m1 x m2 = -1 if a horinzontal line meet v a vertical line,by using same formula ,we hv m1 x m2 = -1 zero x infinity = -1 so..does it make sense??! :eek:

can i ask how do we define infinity? Is it a number that cannot be represented mathematically(like something divided by 0) or is it a number too large that our human mind can't think of? what do statements like 'The universe is infinite' mean? Is it too large to be represented or there are...

hello all another simple question would it be true to say \int_{a_{L}}^{b} f = lim_{k \rightarrow \infty }L(f,P_k) thanxs

This question popped up in my head. What is sin x when x tends to infinity? Since sine is a preiodic functions which repeats itself, is the answer 1, -1 or 0 or something else altogether?

Is \infty - \infty = 0?

Another question from someone who doesn't know much about physics. If black holes don't let light out, then it has to stop somewhere, right? There has to be a point where the light is not moving at c. It's been proven that gravity can "bend" light waves, so why could it not stop them? Also, if...

For those who were on the last thread concerning this, I have started a new one over since the last one is dead. I have thought on the rules for a while, and now have made a few new rules and changed the otherones. For those who have not read the last thread, what I am trying to do is create...

Hey, I'm new here. I wanted to ask a question about infinity - I've been playing with something in my mind. If you define infinity as a number that is greater than all numbers except itself, and negative infinity as a number that is less than all numbers except itself... Couldn't both...

if f(c) = infinity and c is in [a,b] is it equivalent to saying f is not cont. at c ? because infinity is undefined? Thanks k.cv

First, i would have put this in the theory development, but i can't. And since this is pure mathmatical, but i do not know what type, I have put it here. Second, you need to keep an open mind and do not call me crazy. Third, the person who came up with imaginary numbers was probally...

I had a dream this morning about a Stargate type device, and i remembered that a singularity is infinity. And i got to thinking that a black hole is supposed to be a singularity. So is a black hole a physics representation of infinity? and what does that mean?

This is the theory I made, saying that every moment is infidential. Lets just say 1 second can be dividied into 100milliseconds, and 100milliseconds can be divided into the next smallest unit and so, this process is infidential... Same with digits. Lets take an interger 1. We can divide it...

Hello! Here is the problem I am attempting: Sum to infinity: \frac{x}{1*2} + \frac{x^2}{2*3} + \frac{x^3}{3*4} + ... Here is what I get: S = \frac{x^n}{(n)(n+1)} \lim_{n \to \infty} \frac{x^n}{(n)(n+1)}} Now what? Should I do partial fractions to split the equation?

Hey can someone tell me the value of the integral of X^2 exp (-aX^2) dx from zero to infinity. I have the general solution from a table of integrals but since the upper limit is infinity, I can't really plug these numbers in. Can't find it in a table of integrals anywhere? If anyone has the...

I'm having a tough time trying to do integration by parts with one of my limits being infinity. My Integral looks like: \int_0^\infty x^z e^{-x} dx with z = \frac{-1}{\pi} Now if I let u = e^{-x} and dv = x^z dx, I will have: du = -e^{-x} dx and v = \frac{1}{z + 1} x^{z + 1} and...

Human brain is an observer , and the problem of this idea is observing himself the brain will observe an observer observe an observer observe an observer ... to infinity. the real problem appears to people who work in computional simulation of brain ( infinite loop ) can this cycle have any...

Is infinity even or odd? If it's even (or both), then it would mean there's a finitely largest prime. By coarsely applying limit concepts, and lim(x->inf)x/2 does not yield a remainder.

I am a Civil Engineer so I have some college education in mathematics and Calculus. But I am also an old fart so it has been quite a few years since my head had to use this stuff seriously (my work never required it). I tell you this so that you know I am a partial dummy and not a total dummy...

Since the function f(x)=xsin[(pi)x] oscillates, shouldn't the limit as x -> infinity not exist? i was told that it is positive infinity.

x + x = 2x infinity + infinity = 2 infinity (or) infinity x-x=0 infinity * infinity = square of infinity (or) infinity :-p :devil: :blushing: :approve:

Hi I was having a debate with some guys, and anyhow they were saying 0 divided by infinity is 0, and I said that it was undefined. Whose correct? Also, they said infinity divided by a number, say 2, is not infinity, that that is undefined, and I said the number is still infinity. I don;t know...

I've had a discussion with two friends about infinity. I am of the opinion that infinities come in different sizes and some infinities can be bigger than others. My argument goes somewhat like this: Between the numbers 1 and 2 there are infinite real numbers. Between 1 and infinity there are...

I have a few questions regarding infinity. Its pretty long so I thought of putting it up on my site instead of here, sorry about that. The URL is: http://deydas.com/blog/archives/4-What-is-infinity.html . Can anybody answer my question please?! Thank you.

well, yesterday i was talking to my friend, and during the conversation he used the term "almost infinity". though he intended to refer to something very large, but he got me thinking. what is "almost infinity"? or let me rephrase it in a beter way. is it correct to use the term "almost...

Would you please proove that (lim n -> infinity) (1 + 1/n)^n = e ?