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    (Original post by DreamsComeTrue.)
    why? which module you doing at the moment?
    I'm first year uni maths......but somehow having to look through many books to read up on certain parts.....sometimes the notes arent that understandable....
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    (Original post by CKsuper1)
    I'm first year uni maths......but somehow having to look through many books to read up on certain parts.....sometimes the notes arent that understandable....
    oh, i was thinking of doing maths at uni, but a joint module as i wouldn't surive doing a full degree on just maths and yet i couldn't not do maths at all... are you doing an all maths degree? hows it going?
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    (Original post by DreamsComeTrue.)
    oh, i was thinking of doing maths at uni, but a joint module as i wouldn't surive doing a full degree on just maths and yet i couldn't not do maths at all... are you doing an all maths degree? hows it going?
    Aslong as you don't do analysis you'll be fine. Everything else seems rather straight forward in comparison (after doing Math/FMath). I'm sure it will get easier though.
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    (Original post by Ewan)
    Aslong as you don't do analysis you'll be fine. Everything else seems rather straight forward in comparison (after doing Math/FMath). I'm sure it will get easier though.
    argh, i'm not doing further maths! is that a bad thing???
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    (Original post by DreamsComeTrue.)
    argh, i'm not doing further maths! is that a bad thing???
    It will be harder yes. But if the uni doesn't require FMath (they do here), then they should teach you it once you arrive, so not all bad. Just means you'll be learning it in a few weeks rather than a few years :p:
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    (Original post by Ewan)
    It will be harder yes. But if the uni doesn't require FMath (they do here), then they should teach you it once you arrive, so not all bad. Just means you'll be learning it in a few weeks rather than a few years :p:
    i should/ve started doing it in the first place, but i didn't know i would want to do a degree in maths at all! i'll just have to make sure now that all my uni' choices don't want Fmaths otherwise i'm dead..
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    Oh cool........have u dne Q1 part b then? I keep getting other limits like nx etc......
    Nope...Q5 I had a go at.....but really unsure whether its correct....oh...btw, (i'm assuming u've dne 1401), how do u differentiate n times .....?
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    (Original post by DreamsComeTrue.)
    i should/ve started doing it in the first place, but i didn't know i would want to do a degree in maths at all! i'll just have to make sure now that all my uni' choices don't want Fmaths otherwise i'm dead..
    ]

    I don't think many do for combined courses (Maths with...), so you should be ok :p:
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    And btw, Analysis is in all Maths with *** courses....so u cannot avoid it :P

    (at least in UCL anyway)
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    (Original post by CKsuper1)
    Oh cool........have u dne Q1 part b then? I keep getting other limits like nx etc......
    Nope...Q5 I had a go at.....but really unsure whether its correct....oh...btw, (i'm assuming u've dne 1401), how do u differentiate n times .....?
    Differentiate the equation a few times (3/4 times).. off top of my head think it was

    (4-x)y'' + 2y' + Piy
    (4-x)y''' + 4y'' + 2y'' + Piy'
    (4-x)y'''' + 4y''' + 6y''' + Piy''

    Repeat, find a relationship between different differentials... prove the relationship by induction. Done. No I'm just about to start Q1 (b). Q5, prove its a Cauchy sequence like he did in class, thus proving the sequence is convergent.

    (Original post by CKsuper1)
    And btw, Analysis is in all Maths with *** courses....so u cannot avoid it :P

    (at least in UCL anyway)
    Its in most maths and ... courses too I guess they want you to understand where everything comes from...

    (Original post by DreamsComeTrue.)
    i should/ve started doing it in the first place, but i didn't know i would want to do a degree in maths at all! i'll just have to make sure now that all my uni' choices don't want Fmaths otherwise i'm dead..
    Its never too late to start :p:
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    (Original post by DreamsComeTrue.)
    i should/ve started doing it in the first place, but i didn't know i would want to do a degree in maths at all! i'll just have to make sure now that all my uni' choices don't want Fmaths otherwise i'm dead..
    Yh....as Ewan said, for maths and X......most courses are not f.maths only, some just say recommended.
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    (Original post by Ewan)
    Differentiate the equation a few times (3/4 times).. off top of my head think it was

    (4-x)y'' + 2y' + Piy
    (4-x)y''' + 4y'' + 2y'' + Piy'
    (4-x)y'''' + 4y''' + 6y''' + Piy''

    Repeat, find a relationship between different differentials... prove the relationship by induction. Done. No I'm just about to start Q1 (b). Q5, prove its a Cauchy sequence like he did in class, thus proving the sequence is convergent.
    Kool! Was doing it late at night yesterday lol (1401) so i was a bit lazy wi differentiating it so many times haha.....I'll try it out now actually....

    Q5: this is what i have:

    |Xn+1-Xn|<1/(2^n)
    then 1/(2^n) < 1/n

    so we want 1/n < e => n>1/e

    Then choose N = 1/e

    so |Xn+1-Xn| < 1/(2^n)< 1/n < e
    i.e. |Xn+1-Xn| < e for all n>N

    Would this also work? or is it necessary to introduce an 'm'
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    (Original post by CKsuper1)
    Kool! Was doing it late at night yesterday lol (1401) so i was a bit lazy wi differentiating it so many times haha.....I'll try it out now actually....

    Q5: this is what i have:

    |Xn+1-Xn|<1/(2^n)
    then 1/(2^n) < 1/n

    so we want 1/n < e => n>1/e

    Then choose N = 1/e

    so |Xn+1-Xn| < 1/(2^n)< 1/n < e
    i.e. |Xn+1-Xn| < e for all n>N

    Would this also work? or is it necessary to introduce an 'm'
    You need to introduce an m, with that working you aren't proving that x_n is convergent.

    given E>0 you need to find an N, such that m>N and n>N implies |x_n - x_m| < E

    Have you done 3 (c)?

    EDIT: Look at the notes from fridays lecture, after the first part its practically identical minus the |x_2 - x_1| which are in the notes.
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    (Original post by Ewan)
    You need to introduce an m, with that working you aren't proving that x_n is convergent.

    given E>0 you need to find an N, such that m>N and n>N implies |x_n - x_m| < E

    Have you done 3 (c)?

    EDIT: Look at the notes from fridays lecture, after the first part its practically identical minus the |x_2 - x_1| which are in the notes.
    aaah I c.....3(c):

    Well subsequence: X_2n contains all even terms
    and X_2n+1 contains all odd terms

    both subsequences converge to l
    so together, the two subsequences contain all terms in X_n
    i.e. all terms converge to this l


    U think this is a vallid arguement?
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    (Original post by CKsuper1)
    aaah I c.....3(c):

    Well subsequence: X_2n contains all even terms
    and X_2n+1 contains all odd terms

    both subsequences converge to l
    so together, the two subsequences contain all terms in X_n
    i.e. all terms converge to this l


    U think this is a vallid arguement?
    ic... sounds ok. I'm not sure though I'm stuck on 1(b), proving the harmonic mean tends to x as n --> infinity...
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    help, i have another question that needs help!

     y=(x - 1)(2x + 1)^-1
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    I assume that -1 is an exponent?

    Should be (x-1)[-2(2x+1)^{-2}]+(2x+1)^{-1}
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    (Original post by D-Day)
    I assume that -1 is an exponent?

    Should be (x-1)[-2(2x+1)^{-2}]+(2x+1)^{-1}
    yes i did get that, so do you just leave it like that and it doesn't need simplifying? cos i think thats where i go wrong, i try to simplify it and then it goes wrong. lol.

    i simplyfied it to get:

     (2x + 2) (2x + 1) ^-2 + (2x + 1)^-1

    is this wrong?
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    (Original post by DreamsComeTrue.)
    yes i did get that, so do you just leave it like that and it doesn't need simplifying? cos i think thats where i go wrong, i try to simplify it and then it goes wrong. lol.

    i simplyfied it to get:

     (2x + 2) (2x + 1) ^-2 + (2x + 1)^-1

    is this wrong?
    That should be (-2x+2), and you can further simplify it.
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    (Original post by D-Day)
    That should be (-2x+2), and you can further simplify it.
    true.. my mistake, and how would you simplyfy it? its the powers that really confuse me!

    take  (2x + 1)^-1 out of the brackets?
 
 
 

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