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IF you would like help with any math problems, feel free to post them

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    (Original post by Dog4444)
    I found a good problem, but I can't manage to solve it. It supposed to be pretty easy one:

    Prove that there are infinitely many positive integers n such that n^2-1 has a prime divisor greater than  2n+\sqrt{2n}

    Help!
    I don't think this is true....
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    (Original post by TheMagicMan)
    I don't think this is true....
    Definitely true.
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    (Original post by Dog4444)
    Definitely true.
    n^2-1=(n+1)(n-1) so the greatest prime divisor it can have is n+1. As n+1 < 2n for n >1, there are no numbers for which it is true...
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    (Original post by TheMagicMan)
    n^2-1=(n+1)(n-1) so the greatest prime divisor it can have is n+1. As n+1 < 2n for n >1, there are no numbers for which it is true...
    Holy ****
    Typo from me.
    It's n^2+1
    Thousand apologises.
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    (Original post by DFranklin)
    You are reminded to read the Guide to Posting, and in particular what it has to say about posting full solutions.
    Ohh shut up man..seriously..this guy has offered his time, skills and experience in helping the students with maths which they are struggling to complete. A step by step guidance which s/he is actually giving, as well as the answer, personally is also helping me. What's the point in posting how to work something out, and not giving the answer for it...it's called knowing if the student will be right or not? Jesus christ...

    I bet if you were not a moderator and such ignorant on someones offer i.e. the OP, you would be asking the same kind of questions with the request of the answers.


    @Students - Like if you agree to my post.
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    (Original post by FrozenBeak)
    Ohh shut up man..seriously..this guy has offered his time, skills and experience in helping the students with maths which they are struggling to complete. A step by step guidance which s/he is actually giving, as well as the answer, personally is also helping me. What's the point in posting how to work something out, and not giving the answer for it...it's called knowing if the student will be right or not? Jesus christ...

    I bet if you were not a moderator and such ignorant on someones offer i.e. the OP, you would be asking the same kind of questions with the request of the answers.


    @Students - Like if you agree to my post.
    It would have been better had you conveyed your point by being less rude.

    I accept the OP has taken his time to help students. But their are certain flaws of it as well, some students might just give their homework question for the OP to do, and they will then copy without trying to understand it.

    DFranklin is a moderator and its his responsibility to point out if there is a rule being broken. He has to follow the forum rules, and ensure nothing against the rules is posted on the forum.

    Personally, i really appreciate the effort of the OP.

    What's the point in posting how to work something out, and not giving the answer for it
    If you are told the method to work something out, then you should use that method to work out the answer, and then tell your answer so that others can check and inform if you are right or wrong.

    And IT WILL BE BETTER IF YOU KEEP YOUR OPINIONS TO YOURSELF, SUCH POSTS WON'T HELP ANYONE.
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    (Original post by raheem94)
    It would have been better had you conveyed your point by being less rude.

    I accept the OP has taken his time to help students. But their are certain flaws of it as well, some students might just give their homework question for the OP to do, and they will then copy without trying to understand it.

    .
    Top notch at maths, but terrible English.
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    (Original post by Brit_Miller)
    Top notch at maths, but terrible English.
    Everybody can make mistakes, i didn't read it well, to eliminate mistakes.
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    (Original post by raheem94)
    Everybody can make mistakes, i didn't read it well, to eliminate mistakes.


    Just ribbing, fella.
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    I was wondering if someone could please help me with part B of following C2 log question attached as I'm not sure how to go about solving it.

    Thanks
    Attached Thumbnails
    Click image for larger version. 

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    Use (a) to substitute the LHS

    remove the logs

    you have simultaneous equations
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    How can I prove that this has no solutions for n=3,4,5... where x,y and z are integers?

    \displaystyle x^n+y^n=z^n
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    (Original post by oh_1993)
    How can I prove that this has no solutions for n=3,4,5... where x,y and z are integers?

    \displaystyle x^n+y^n=z^n
    Ok, I got it.
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    (Original post by sulexk)
    Hi,

    That is to do with functions of complex variables. I will try and work on it, although have not yet covered Functions of Complex variables. Will try soon though!
    I would love to work on these in the summer, once all exams are done.
    Just want to make sure that you know; that is the Riemann Hypothesis and hasn't be solved for over 150 years and counting.

    But you could try
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    When Sulexk manages to solve all the problems in this thread and becomes famous around the world, we can all look back at this thread and remember that "this was where it all started".
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    (Original post by Dog4444)
    Ok, I got it.
    :qed: ?
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    http://www.thestudentroom.co.uk/show....php?t=1969325
    My q is up here ... please can u help me ??
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    Hi, working on this q for a while... needhelp please...

    A heaving ring of mass 5 kg is threaded on a fixed rough rod. Coefficient of friction between rod and ring is 1/2... A light string is attatched to the string and pulled down at 30 degrees to the horizontal. The magnitude of force T from the light rope is increases from 0. Find the value of T that is just suffiecient to make the equilibrium limiting..

    I worked out friction was 24.5 (5x9.8x0.5)
    Then I worked out the the horizontal force of the string would be Tcos(30)
    So i did
    Tcos(30)- 24.5 = 0
    Thus, T =28.3 N
    The answer is actually 39.8... Where am i going wrong please??
    Click image for larger version. 

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    Been stuck on this one all day:

    Is it true that every problem whose solution can be quickly verified by a computer can also be quickly solved by a computer?


    Spoiler:
    Show
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    (Original post by oh_1993)
    How can I prove that this has no solutions for n=3,4,5... where x,y and z are integers?

    \displaystyle x^n+y^n=z^n
    I have an elegant proof but this post is not large enough to contain it.

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Updated: April 17, 2012
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