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    (Original post by Revd. Mike)
    I felt mildy nauseous just looking it up :p:
    ;.; It's horrible. And evil. And stuff. And it makes me wanna cry cos I thought I understood but now I can't do the questions and the exam is on Monday
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    (Original post by Rainfaery)
    ;.; You don't happen to properly understand index notation and the Levi-Civita symbol, do you?
    I did understand it last year. What about it do you not understand? Give me an example
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    (Original post by Gesar)
    I did understand it last year. What about it do you not understand? Give me an example
    I'm working on the problem that I've posted about here: http://www.thestudentroom.co.uk/show...9#post25164679

    Except I can't make the LaTeX work on TSR for some reason. >.< The code compiles fine on my laptop...
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    (Original post by Rainfaery)
    I'm working on the problem that I've posted about here: http://www.thestudentroom.co.uk/show...9#post25164679

    Except I can't make the LaTeX work on TSR for some reason. >.< The code compiles fine on my laptop...
    Well, I can't use LaTeX at all, so you'll have to make do with makeshift notation...

    You have

    e(ijk)e(klm)a(k)b(l)c(m)=a(j)b(j )b(i)-a(k)b(k)c(i)

    But it -should- be:

    e(ijk)e(klm)a(j)b(l)c(m)=a(j)c(j)b(i)-a(k)b(k)c(i)

    (You had 3 k's in one term, a big no-no).

    And now, you just have to mess around with it for a bit. What do you need e(ijk)e(klm) to equal if you want the LHS to equal the RHS?

    The first term on the RHS indicates you want j turned into j, l turned into i and m turned into j. (This is going from the RHS to the LHS). And the second term says you need j and l turned into the same thing, and m turned into i. (Essentially, stare at RHS and decide which letters you need to change to make it match the LHS).

    So, try e(ijk)e(klm)=(d(li)d(jm)-d(mi)d(jl)), which is what you needed, I think...
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    (Original post by dbmag9)
    Hmm, looks like the new coalition will be more stable than I expected. Amusing first press conference though


    The new equality minister appears to be a bit of a fail on the equality front, from what I gather from more queer-politically minded acquaintances.

    DAMN I SHOULD BE REVISING. :eek:
    Yeah, I've been ranting about it on facebook all day. I mean, Cameron's voting record on LGBT issues is bad, but she's something else. Oh and she's in favour of fox hunting. She sounds lovely. There seems to be a bit of a trend of giving the Equality post to someone who's a teensy bit mental/not in favour of equality (like Ruth Kelly).
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    (Original post by icysquall)
    Yeah, I've been ranting about it on facebook all day. I mean, Cameron's voting record on LGBT issues is bad, but she's something else. Oh and she's in favour of fox hunting. She sounds lovely. There seems to be a bit of a trend of giving the Equality post to someone who's a teensy bit mental/not in favour of equality (like Ruth Kelly).
    "Moderately against" gay rights, didn't bother voting on trans recognition, ist just about OK with civil partnerships. This is what comes of making them appoint the cabinet when they've had no sleep for days.

    I'm hoping she's so busy being Home Secretary that some Lib Demmer can come in and sort out some proper equality.
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    (Original post by Gesar)
    Well, I can't use LaTeX at all, so you'll have to make do with makeshift notation...

    You have

    e(ijk)e(klm)a(k)b(l)c(m)=a(j)b(j )b(i)-a(k)b(k)c(i)

    But it -should- be:

    e(ijk)e(klm)a(j)b(l)c(m)=a(j)c(j)b(i)-a(k)b(k)c(i)

    (You had 3 k's in one term, a big no-no).

    And now, you just have to mess around with it for a bit. What do you need e(ijk)e(klm) to equal if you want the LHS to equal the RHS?

    The first term on the RHS indicates you want j turned into j, l turned into i and m turned into j. (This is going from the RHS to the LHS). And the second term says you need j and l turned into the same thing, and m turned into i. (Essentially, stare at RHS and decide which letters you need to change to make it match the LHS).

    So, try e(ijk)e(klm)=(d(li)d(jm)-d(mi)d(jl)), which is what you needed, I think...
    Ah yeah, those bits you pointed out were silly typos. :blushing: I had it written down right on my paper, heh. I think I just hit a mental block at that point; I didn't think of just sort of trial and erroring to get the right combination of deltas.

    Thanks for the help.
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    The conservatives are making me sad already :sad: <-- See?
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    (Original post by Rainfaery)
    Ah yeah, those bits you pointed out were silly typos. :blushing: I had it written down right on my paper, heh. I think I just hit a mental block at that point; I didn't think of just sort of trial and erroring to get the right combination of deltas.

    Thanks for the help.
    There's undoubtedly a clever way to do it :p: But they clearly weren't gunning for the clever way because they gave you the identity that you usually prove via the result you were asked to deduce.
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    (Original post by Gesar)
    The conservatives are making me sad already :sad: <-- See?
    :sad: I was reading what the Tories have conceded to get the coalition to work and it's really not very much (they've kept a number of policies which I really hate). *sigh* I had hoped that the Lib Dems hadn't surrendered too much of their integrity.
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    The Conservatives are already making me angry; I've more or less skipped being sad and gone straight to rage.
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    (Original post by Gesar)
    There's undoubtedly a clever way to do it :p: But they clearly weren't gunning for the clever way because they gave you the identity that you usually prove via the result you were asked to deduce.
    Yeah, that's true. All my other exams are about clever ways, and this one is just...not, I suppose. Threw me off a bit. XD I was getting all panicked because I had thought I totally understood index notation, and then I got all stuck here.

    How are you doing in general? I've not spoken to you in ages!
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    (Original post by Laertes)
    The Conservatives are already making me angry; I've more or less skipped being sad and gone straight to rage.
    I'm just laughing at the fact we all now have to put up with liberals...
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    Perhaps this will make someone chuckle...

    I got a message off someone on TSR asking me how hung I was.

    I am as hung as the parliament in this country - greater than the majority.
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    (Original post by Spacecam)
    Perhaps this will make someone chuckle...

    I got a message off someone on TSR asking me how hung I was.

    I am as hung as the parliament in this country - greater than the majority.
    :toofunny:

    You should respond.
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    (Original post by Lord Hysteria)


    You should respond.
    The reply was mine!
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    (Original post by Spacecam)
    Perhaps this will make someone chuckle...

    I got a message off someone on TSR asking me how hung I was.

    I am as hung as the parliament in this country - greater than the majority.
    Awesome.
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    (Original post by Spacecam)
    Perhaps this will make someone chuckle...

    I got a message off someone on TSR asking me how hung I was.

    I am as hung as the parliament in this country - greater than the majority.
    *snigger*

    You win.
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    (Original post by Spacecam)
    Perhaps this will make someone chuckle...

    I got a message off someone on TSR asking me how hung I was.

    I am as hung as the parliament in this country - greater than the majority.
    Does the parliament still count as hung, now that we have a government of sorts?

    Gah, Tim Minchin is not good for starting some revision...
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    (Original post by dbmag9)
    Does the parliament still count as hung, now that we have a government of sorts?
    No, a majority has been achieved so it's back to a relative norm.
 
 
 
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