Math question

Discussion in 'General Off-Topic Chat' started by jumpman17, Feb 12, 2007.

Feb 12, 2007

Math question by jumpman17 at 5:40 PM (1,788 Views / 0 Likes) 21 replies

  1. jumpman17
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    Former Staff jumpman17 He's a semi-aquatic egg laying mammal of action!

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    The forumla:
    m-M = 5log(d)-5

    Now, does that mean I take the log of just d or do I take the log of d-5?
     


  2. Veho

    Global Moderator Veho The man who cried "Ni".

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    If only the d is in brackets, then you only take the logarithm of d.

    I suppose the (d - 5) is less than zero in this case?
     
  3. Issac

    Member Issac Mini-mod

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    that means log(d) ... THEN minus 5

    EDIT: You beat me to it [​IMG]

    (Talking about math, I hate it [​IMG], or.... well it's hard)
     
  4. mcbey

    Member mcbey GBAtemp Regular

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    Sorry for asking but what branch of math is this?
     
  5. FAST6191

    Reporter FAST6191 Techromancer

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    For what it is worth +1 to Issac and veho, some people do not like it but if you think about having constants or negatives first it reduces the chances of a mistake.
    @mcbey it could be many things but it looks like plain logarithms/exponential which are in fact an exceptionally important area.
     
  6. Issac

    Member Issac Mini-mod

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    Yes, I must say logarithms and exponential functions are very important if you are planning to study at an university or such a place.

    liniear algebra has been the hardest part so far... yuck!

    Now we are playing with differentiation... like... Derivatives and anti derivatives... quite easy! [​IMG]
     
  7. jumpman17
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    Former Staff jumpman17 He's a semi-aquatic egg laying mammal of action!

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    Thanks for the answers.

    This is for my astronomy class. Where m = the apparent magnitude of a star, M = the absolute magnitude of a star, and d = the distance in parsecs.

    EDIT: Derivatives and anti-derivatives, I just had those last semester in Technical Calculus I. And they keep popping up in my Physics I class this semester too.
     
  8. butaro

    Member butaro GBAtemp Regular

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    laplace transforms are fun as are maclauren series and his friends
     
  9. Issac

    Member Issac Mini-mod

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    ooh okay... this course is roughly translated to single variable analysis.. or something... [​IMG] math...

    We will have physics I this autumn... [​IMG]
     
  10. Veho

    Global Moderator Veho The man who cried "Ni".

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    Around here it's called mathematical analisys 1.
    M.A. 2 would be multiple-variable functions, and M.A. 3 is complex variable functions.

    And then there's Discrete maths (discrete/non-continuous functions), Numeric maths (interpolations, extrapolations, approximations, iterations, in short, ways to calculate decimal equivalents of discrete expressions, like pi/4 or log(75.2) and stuff), Stohastic maths (probability and combinatorics), Linear Algebra (matrices and vectors and linear operators), and chaos theory (everything).
     
  11. Issac

    Member Issac Mini-mod

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    Linear Algebra is so hard.. even to think about it is hard... to calculate a vector in a 7-dimensional room.... it's much easier to just process the numbers, than to try to understand it all.
    But right now it's useful, and much easier to grasp, when using MatLab. Studying Hamming Codes now... THAT is much fun!
     
  12. Veho

    Global Moderator Veho The man who cried "Ni".

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    Yeah, well, it's easier since Matlab has functions that do all the meticulous calculation for you. For me, the hardest part of linear algebra is wrangling all those numbers... I always make mistakes when I try doing it "on foot"...

    "Calculate A^4 when A is a 6x6 matrix with the elements as shown in Fig. 3.2. .... Use of calculators is prohibited... " [​IMG]
     
  13. Issac

    Member Issac Mini-mod

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    ouch.. that's just mean!
    Well, we aren't allowed to use calculators either... but when using matlab, you get a new perspective at it (we use it in a different course, with a lot of linear algebra implemented in it all).

    Hamming Codes, if you havn't already, maybe you will, come across that... I think it's really interesting.
    (self "correcting" codes...)

    http://en.wikipedia.org/wiki/Hamming_Code
     
  14. Psyfira

    Member Psyfira Credit: 0ml. Insert tea to continue

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    [Edit] Forget I asked, one look at Wikipedia and I've gone all "urk crazymaths!" [​IMG]
     
  15. Smack

    Member Smack GBAtemp Regular

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    You are doin Linear right now as well eh? I may have to remember this for when I am tearing my hair out. We are just covering vector spaces in n-dimensions right now and the theory you need to know for this subject makes your brain wanna explode. I truly envy anyone that can easily grasp this stuff as most of the people I know who are taking it or have taken it do not.
     
  16. Icarus

    Member Icarus fire walk with me

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    If you had to take the log of d-5, it would've been log(d-5) no ? Then it's just log of d and minus 5.. Don't you have it written on a paper ? It's freaking hard to type math stuff on computer !!
     
  17. Nevin007

    Member Nevin007 GBAtemp Regular

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    Hahaha Linear Algebra was sooo easy at University of Michigan - Dbn. I waited a week before the test to even START the homework problems and I got an A in the class. Now what's difficult is this chapter I'm doing now "Fourier Representations of Signals and Systems". Now that's hard stuff. The chapter is 82 pages, almost all formulas!!!
     
  18. 2cb2ct7

    Member 2cb2ct7 GBAtemp Advanced Fan

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    God bless you hardcore maths nerds! I'm a chemist but I have a fellow chemist friend who only enjoys maths once you reach the level where they stop using numbers to represent anything. She misses her 3rd year advanced maths lectures.
     
  19. Issac

    Member Issac Mini-mod

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    I'm not doing Linear now, I did a few months ago. Now we have the analysis course, which is rather easy right now, and we have, at the same time, an "applied mathematics to nature sciense and techniques" or something... (the MatLab course).

    and the third and last one we are doing at the moment is Java programming... rather boring though.
     
  20. Veho

    Global Moderator Veho The man who cried "Ni".

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    We covered that in another subject... Digital Electronics. Logical circuits, binary code, redundant coding, self-correcting coding, multi-parity coding, cross-parity coding, and the implementation of all that into electronical circuitry. More transistor switches than you can shake a stick at [​IMG]
     

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