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    (Original post by joostan)
    i^2=-1
    :O thank you I had do idea lols, OMFG I actually understood your proof !
    Getting used to it :P

    (Original post by Robbie242)
    It's an imaginary number

    it is denoted as i=\sqrt{-1}

    If you do FP1 onwards you'll come across them all the time
    Ahh thank you, I only do c1-c4 and s1-s2 although I shall remember that for future reference
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    (Original post by tigerz)
    :O thank you I had do idea lols, OMFG I actually understood your proof !
    Getting used to it :P
    Meh - there's probs a better (more rigourous) way but I'm lazy
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    (Original post by joostan)
    Brain dead after 3 hours of bio so I'll do this the lazy way - Proof by example.
    Spoiler:
    Show
    So:
    x = a^2 + b^2

y = c^2 + d^2

z=ac+bd
    Considering the given equation, and subbing in the solutions.
    xy=z^2+1 \ (*)

\Rightarrow (a^2+b^2)(c^2+d^2) = (ac+bd)^2+1

\Rightarrow a^2c^2+b^2c^2 + a^2d^2 +b^2d^2 = a^2c^2+2abcd+b^2d^2+1

\Rightarrow (bc-ad)^2=1
    Let:
    b=2, \ c=3, \ a=5, \ d=1
    Sub into (*)
    (5^2+2^2)(3^2+1^2) =(15+2)^2+1

\Rightarrow 290 = 290
    So some integers exist that satisfy the equation.
    Solutions may be found using the expression derived.
    At least you bothered to find some decent numbers, I was even lazier and set a=0, b=1, c=1, d=0 :lol:
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    (Original post by justinawe)
    At least you bothered to find some decent numbers, I was even lazier and set a=0, b=1, c=1, d=0 :lol:
    Yeah but I figured they should all be distinct, though it wasn't specified
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    (Original post by joostan)
    Meh - there's probs a better (more rigourous) way but I'm lazy
    shh, I understood it this way :') Although I would of only managed to do the first 3 lines of proof on my own!
    *must revise chem* >.<
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    (Original post by tigerz)
    shh, I understood it this way :') Although I would of only managed to do the first 3 lines of proof on my own!
    *must revise chem* >.<
    Keep telling yourself that - you may actually do some
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    (Original post by joostan)
    Yeah but I figured they should all be distinct, though it wasn't specified
    I can set a=0, b=1, c=-1 and d=anything, no big deal :dontknow: there's always room to be even lazier
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    (Original post by joostan)
    Keep telling yourself that - you may actually do some
    Haha, between sat and today I've done 3 papers, when I did maths revision I would do 3 a day!
    Plus I managed good scores for 2 and got a C in another >.< I've gotta step up my game
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    (Original post by justinawe)
    I can set a=0, b=1, c=-1 and d=anything, no big deal :dontknow: there's always room to be even lazier
    Yes, but you've not got a pretty function

    (Original post by tigerz)
    Haha, between sat and today I've done 3 papers, when I did maths revision I would do 3 a day!
    Plus I managed good scores for 2 and got a C in another >.< I've gotta step up my game
    :lol: You'll be fine
    Chem's nice but maths revision is by far and away the best
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    (Original post by tigerz)
    Haha, between sat and today I've done 3 papers, when I did maths revision I would do 3 a day!
    Plus I managed good scores for 2 and got a C in another >.< I've gotta step up my game
    Well that's more than I've been doing for the last 2 years! I think the most I do of 1 thing is about 2 papers, even if the exam is only a few days away


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    (Original post by tigerz)
    shh, I understood it this way :') Although I would of only managed to do the first 3 lines of proof on my own!
    *must revise chem* >.<
    tbh the only part that was really a "proof" was subbing in the values, the rest was just simplifying the equation
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    (Original post by MathsNerd1)
    Well that's more than I've been doing for the last 2 years! I think the most I do of 1 thing is about 2 papers, even if the exam is only a few days away


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    I don't think I've ever done a full past paper for maths before
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    (Original post by justinawe)
    I don't think I've ever done a full past paper for maths before
    Except the ones you do as mocks and the actual exams too?


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    (Original post by MathsNerd1)
    Except the ones you do as mocks and the actual exams too?


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    My teachers normally give mixed past paper questions as mocks :lol: actual exams are "present papers", not "past papers" :sly:
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    (Original post by justinawe)
    My teachers normally give mixed past paper questions as mocks :lol: actual exams are "present papers", not "past papers" :sly:
    Really? That'd be more effective I feel and that's very true, thought I could catch you off guard


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    (Original post by joostan)
    Yes, but you've not got a pretty function


    :lol: You'll be fine
    Chem's nice but maths revision is by far and away the best
    Yup, I'll be asking for some lovely maths problem from the 10th of June!
    (Original post by MathsNerd1)
    Well that's more than I've been doing for the last 2 years! I think the most I do of 1 thing is about 2 papers, even if the exam is only a few days away


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    Past Papers is how I revise! I can't get my head around just reading notes (short attention span, i'm reading but i'm not)

    (Original post by justinawe)
    tbh the only part that was really a "proof" was subbing in the values, the rest was just simplifying the equation
    Yeah, the question looked worse than it was!

    (Original post by justinawe)
    I don't think I've ever done a full past paper for maths before
    P.S. I envy you...
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    (Original post by tigerz)
    Yeah, the question looked worse than it was!



    P.S. I envy you...
    The secret is to never be intimidated by how hard a question appears to be, just get into it!

    How come? :holmes:
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    (Original post by justinawe)
    The secret is to never be intimidated by how hard a question appears to be, just get into it!

    How come? :holmes:
    LOOL, thats exactly why, certain questions just look 'unsolvable' to me! I don't know how to approach them, I is lacking experience :yep:
    You've never done a full maths paper! (apart from exam) that's crazy lmao, our teachers are too lazy to make their own mixed questions, only chem teachers do it, sometimes economics
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    (Original post by MathsNerd1)
    Well that's more than I've been doing for the last 2 years! I think the most I do of 1 thing is about 2 papers, even if the exam is only a few days away


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    Well, this makes the 40 odd past papers I did for M1 alone seem rather silly.
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    (Original post by DJMayes)
    Well, this makes the 40 odd past papers I did for M1 alone seem rather silly.
    I did around 50 papers for C1! :ashamed:
 
 
 
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