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Maths HL proofs

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  • 05-06-2008 4:28pm
    #1
    eoin2nc
    Registered Users Posts: 688 ✭✭✭


    Any tips or ideas on which proofs might show up tomorrow?


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    #2
    Cokehead Mother
    Closed Accounts Posts: 773 ✭✭✭Cokehead Mother


    I don't think I've seen the quotient rule proof before. We're supposed to know that, right?


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    #3
    eoin2nc
    Registered Users Posts: 688 ✭✭✭eoin2nc


    I think so. Theres just so many x and h flying around that I always get lost in it!


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    #4
    Cokehead Mother
    Closed Accounts Posts: 773 ✭✭✭Cokehead Mother


    eoin2nc wrote: »
    I think so. Theres just so many x and h flying around that I always get lost in it!

    Yeah. I think if it comes up I'll just prove the product rule and derive the quotient rule from that.


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    #5
    turgon
    Closed Accounts Posts: 3,762 ✭✭✭turgon


    Learn 'em all


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    #6
    turgon
    Closed Accounts Posts: 3,762 ✭✭✭turgon


    Cokehead Mother wrote: »
    Yeah. I think if it comes up I'll just prove the product rule and derive the quotient rule from that.

    How does that work?


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    #7
    Fuascailt
    Closed Accounts Posts: 268 ✭✭Fuascailt


    Not many for tommorrow, is there? Factor theorem, De moivres, and the differentiation ones (sum/diff, prod/quotient and the induction one) Is that it?


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    #8
    Cokehead Mother
    Closed Accounts Posts: 773 ✭✭✭Cokehead Mother


    turgon wrote: »
    How does that work?

    y = u/v so u = vy and then you use the product rule to find du/dx and you fiddle around a bit. It's probably longer but I think it's less nasty.


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    #9
    eoin2nc
    Registered Users Posts: 688 ✭✭✭eoin2nc


    Fuascailt wrote: »
    Not many for tommorrow, is there? Factor theorem, De moivres, and the differentiation ones (sum/diff, prod/quotient and the induction one) Is that it?

    Is that all? Ive been skipping tham all year because I hate them! Are any of them just going to come up in Q5 or can I expect them to be in any question?
    TBH there simple enough but it would take a while just to get them fully right


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    #10
    Cokehead Mother
    Closed Accounts Posts: 773 ✭✭✭Cokehead Mother


    eoin2nc wrote: »
    Is that all? Ive been skipping tham all year because I hate them! Are any of them just going to come up in Q5 or can I expect them to be in any question?
    TBH there simple enough but it would take a while just to get them fully right

    Q5 might ask you to prove one of the S&S formulae but it's just straightforward induction.


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    #11
    Fuascailt
    Closed Accounts Posts: 268 ✭✭Fuascailt


    I dont have questions 4 or 5! sorry :)


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    #12
    turgon
    Closed Accounts Posts: 3,762 ✭✭✭turgon


    Cokehead Mother wrote: »
    y = u/v so u = vy and then you use the product rule to find du/dx and you fiddle around a bit. It's probably longer but I think it's less nasty.

    Works a treat. Is that allowed in the exam, are you allowed assume the product rule?? Or would you have to prove that first?


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    #13
    Cokehead Mother
    Closed Accounts Posts: 773 ✭✭✭Cokehead Mother


    turgon wrote: »
    Works a treat. Is that allowed in the exam, are you allowed assume the product rule?? Or would you have to prove that first?

    You'd need to prove the product rule first.


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    #14
    turgon
    Closed Accounts Posts: 3,762 ✭✭✭turgon


    It would probably take longer in the long run then.


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    #15
    NanoZoom555
    Closed Accounts Posts: 21 ✭NanoZoom555


    would is not just be way simpler to do it out the normal way?
    our teacher thinks the proof by induction of de moivres theorem could come up in Q.3 as well.


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    #16
    GLaDOS
    Moderators, Regional East Moderators Posts: 23,212 Mod ✭✭✭✭GLaDOS


    Differentiation proof by induction came up 2 years ago so I reckon thats safe, other proofs are easy

    Cake, and grief counseling, will be available at the conclusion of the test



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