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#1 2013-01-30 03:56:56

mttal24
Member
Registered: 2012-05-01
Posts: 23

Limits n->infinity questions on factorials

I am trying to solve questions like:

1.


and
2.

How do I solve them?
for the first one, i get upto lim 1/n+2. Then what should I do?

Last edited by mttal24 (2013-01-30 03:57:36)

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#2 2013-01-30 04:03:46

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,269

Re: Limits n->infinity questions on factorials

hi mttal24

Yes, so you have done it because that fraction tends to zero as n tends to infinity.

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#3 2013-01-30 04:11:32

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Hi mttal24;

This one is good to memorize

for c is any constant.

The second one is a little tougher.

When reduced it becomes:

which you can now use l'Hopitals rule on. Or you can make use of a very important formula.

when n < m.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#4 2013-01-30 04:55:05

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

Your last formula should have x  tebd to infinity, because otherwise it is infinity...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#5 2013-01-30 04:58:44

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Yes, I know it was a latex error, I have corrected it while you were posting.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#6 2013-01-31 01:58:55

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

That is okay now.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#7 2013-01-31 02:02:13

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

That is okay now.

Hmmmm.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#8 2013-01-31 02:04:32

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

What?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#9 2013-01-31 02:09:13

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Nothing, I was just going Hmmmm.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#10 2013-01-31 02:25:44

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

I know, but that usually has more to it than just saying ’Hmmmm’ for no reason...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#11 2013-01-31 03:20:42

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

The closer we get to 2 / 5 / 2013 the more hmmmming I will be doing.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#12 2013-01-31 03:37:08

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

5th of February? Why?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#13 2013-01-31 03:44:44

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

http://www.mathisfunforum.com/viewtopic … 67#p201867

post #439.

That post was made on 2 / 12 / 2012 and was a Sunday. The poster mentions the Sunday before, that makes 2 / 5 / the pivotal day.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#14 2013-01-31 07:53:56

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

That post was on 18th, which makes 12th the pivotal day...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#15 2013-01-31 08:08:47

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Oh yes, the 12th. That will come around pretty quick.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Offline

#16 2013-01-31 08:11:14

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

Yeah, but it's nothing special...


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#17 2013-01-31 08:20:04

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Why isn't it special?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#18 2013-01-31 08:23:55

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,885

Re: Limits n->infinity questions on factorials

Why should it be?

And wouldn't it be better to continue in the Chatter?


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#19 2013-01-31 08:26:02

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Nothing to continue about. I will make a forum announcement on that day.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#20 2013-02-01 02:04:14

mttal24
Member
Registered: 2012-05-01
Posts: 23

Re: Limits n->infinity questions on factorials

Wow! A lot of discussions on hmms.. in this post.
Now, the answer in the book says that the answer for question (1) is 1/2.
Is it right or there is a printing mistake?

Last edited by mttal24 (2013-02-01 02:06:13)

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#21 2013-02-01 02:06:14

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Hi;

For which one?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Offline

#22 2013-02-01 02:07:26

mttal24
Member
Registered: 2012-05-01
Posts: 23

Re: Limits n->infinity questions on factorials

^^just edited my earlier post. It is for the first one.

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#23 2013-02-01 02:10:30

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Hi;

Must be a typo, both of those limits are 0.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Offline

#24 2013-02-01 02:11:31

mttal24
Member
Registered: 2012-05-01
Posts: 23

Re: Limits n->infinity questions on factorials

Thanks!

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#25 2013-02-01 02:13:15

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 83,032

Re: Limits n->infinity questions on factorials

Hi;

You are welcome.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Offline

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