Secondary Maths questions, give me your maths questions

Discussion in 'Education and Employment' started by Nasma, Aug 29, 2009.

Put it out there
  1. Nasma

    Nasma Team Captain

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    I'm currently desperately searching for ways to procrastinate, so help me. If you have any maths questions, ask, and I'll do my best to answer. This means:

    - Actual questions, i.e. "What is the integral of sin(x).exp(x)?"

    - Explanations, i.e. "Why does the quadratic formula work?", "How can I tell the difference between continuous data and discrete data?"

    - Tips, i.e. "What's a good way to stop making this mistake?"

    - Anything else you can think of

    If you can let me know if my response was helpful, that'd be great too.

    Good luck on exams.

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  2. mdc

    mdc Account Cancelled by User

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    Sympathy post :)

    Here's a nice spec. maths problem:

    Take an arbitrary quadrilateral. Attach a square to each side such that the side-lengths of the squares are equal to the appropriate side-length of the quadrilateral. Pictorially:

    [​IMG]

    Draw lines connecting the centres of opposite squares as shown above. Show that the lines have the same length and are perpendicular.
  3. scooterselwood

    scooterselwood Team Captain

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    If x+5=11 what is x?
  4. i_love_the_hoff

    i_love_the_hoff Draftee

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    :eek:......6
  5. Colin D'Cops

    Colin D'Cops Club Legend

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    That shit I learnt in primary school.

    Anyway, x = 6. (6 + 5 = 11)
    Rahul likes this.
  6. scooterselwood

    scooterselwood Team Captain

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    Im surprised you did learn, cause you were silly enough to think I was serious...
  7. Colin D'Cops

    Colin D'Cops Club Legend

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    Yeah cause it's easy to tell on a compter screen isn't it? Tool.

    Wouldn't surprise me if you were actually serious to be honest.
  8. DamianBis

    DamianBis Team Captain

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    x-9000=1

    It's over 9000
  9. ToroHombre

    ToroHombre Team Captain

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  10. Colin D'Cops

    Colin D'Cops Club Legend

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    Haha, nice find there. :D
  11. i_love_the_hoff

    i_love_the_hoff Draftee

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    pythagoras.....my favourite :D

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  12. doggiesin08

    doggiesin08 All Australian

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  13. mdc

    mdc Account Cancelled by User

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  14. icetea

    icetea Senior List

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    prove that no 3 postive integer a, b, and c can satisfy the equation a^n+b^n=c^n for any integer value of n greater than 2. :D
  15. TheBigT

    TheBigT Team Captain

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    still have bad memories of watching a video regarding that last year.
  16. icetea

    icetea Senior List

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    haha same here, i find it amazing how such a seemingly easy problem was so hard to prove. it took this mathematician 7 years to work out a proof :S.
  17. mdc

    mdc Account Cancelled by User

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    "It took mathematicians around the world hundreds of years of failure before someone was able to prove it" would be closer to the mark.
  18. SJ

    SJ Moderator

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    Why does e^(pi*i) = -1?
  19. mdc

    mdc Account Cancelled by User

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    e^(x*i) = cos(x)+isin(x)

    e^(pi*i) = cos(pi) + isin(pi) = -1 + i*0 = -1
  20. SJ

    SJ Moderator

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    That's right. Maybe "why" isn't the correct question, as I understand the algebra. I haven't studied mathematics since second year - how does e^(x*i) = cos(x)+isin(x) again?
  21. mdc

    mdc Account Cancelled by User

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    You can think of it as a notational convenience, or otherwise expand cos(x), isin(x) and e^(x*i) as Taylor Series in the complex plane and see that it holds.
  22. SJ

    SJ Moderator

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    That's it. Euler's identity is an amazing bit of mathematical beauty in any case.
  23. Colin D'Cops

    Colin D'Cops Club Legend

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    [​IMG]

    :D
  24. SJ

    SJ Moderator

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    Don't get it.

    If you mean that I don't know what I'm talking about, you're only half right. I've studied advanced first year maths and also second year engineering maths at university. I have written a proof on the identity before too, I just couldn't remember the principles behind it.

    Thanks mcd.
  25. Colin D'Cops

    Colin D'Cops Club Legend

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    Not quite mate. Nothing to do with your knowledge of maths.

    Just the two words 'mathematical' & 'beauty' look strange in the same sentence from my perspective; far from beauty IMO. :p