Can you solve it?

Discussion in 'General Off-Topic Chat' started by MaHe, Apr 21, 2008.

  1. MaHe
    OP

    MaHe one lazy schmo

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    Here's a little math problem. Let's see if you can actually solve it. [​IMG]
    While I know the solution, I have no idea how to reach it by calculation (I guessed [​IMG] ).

    a = c2d + c2
    b = cd + a:b
    c = a - b - cd
    d = ((c+c+c):c):c

    Figure out the values of a, b, c and d. Only one solution is possible.
    And just to clarify ":" means to divide.

    EDIT: Holy crap, wrong forum. >_
     
  2. King Zargo

    King Zargo I'm a Star

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    I wont help you on your homework.
     
  3. xcalibur

    xcalibur Gbatemp's Chocolate Bear

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    Then why the hell did you bother posting?

    Anyways, I would imagine you would have to put answers in terms of other words.
    e.g c+c+c=3c, 3c:c = 3, 3:c=d

    and just workd your way up by just putting stuff in terms of others.
     
  4. MaHe
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    MaHe one lazy schmo

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    This is not my homework, I made the equations ... Just modified one that I was able to solve and added a twist ...
    Warning: Spoilers inside!
    And please, can a mod move this to another forum?
     
  5. Sonicslasher

    Sonicslasher In Law we trust.

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    muV 2 tIsTiNG aReA!!!111
     
  6. Psyfira

    Psyfira Credit: 0ml. Insert tea to continue

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    Been a while, heh,I just proved that b=b [​IMG] Useful much?
     
  7. Linkiboy

    Linkiboy GBAtemp Testing Area

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    For the calculation, just replace the variables with equivalents. since d = *long equation here* just plug it into a so you have two variables etc im too lazy
     
  8. Artheido

    Artheido GBAtemp Fan

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  9. arctic_flame

    arctic_flame GBAtemp ATMEGA8 Fan

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    Yes.
     
  10. deathfisaro

    deathfisaro Narcistic Deathfisaro Fan

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    a = c^2d + c^2
    b = cd + a/b
    c = a - b - cd
    d = ((c+c+c)/c)/c

    d = 3/c
    substitute d = 3/c
    a = 3c + c^2 (1)
    b = 3+ a/b -> b^2 = 3b + a, a = b^2 - 3b (2)
    c = a - b - 3 (3)

    combine (1) and (2)
    3c + c^2 = b^2 - 3b (4)

    substitute (2) into (3)
    c = b^2 - 3b - b - 3 = b^2 - 4b - 3 (5)

    substitute (5) into (4)
    (b^2 - 4b - 3)*(b^2 - 4b) = b^2 - 3b

    You get
    b(b^3 - 8b^2 + 12b + 15) = 0,
    so if b = 0, then c^2d + c^2 = c^2d, so c =0, then d = 0/0 which isn't desirable so b=/=0
    That means b^3 - 8b^2 + 12b + 15 = 0
    because 15 has factors of 1,3,5,15, try factoring with (b-1), doesn't work. (b-3) doesn't work,
    Factor with (b-5) you get (b-5)(b^2-3b-3) = 0
    so if b = 5, then c = 25-20-3 = 2 from (5), then a = 3*2 + 2^2 = 10 from (1), and d = 3/2.
    (The only way to factor out b^2 - 3b - 3 is factoring by (b-1) and (b-3), and we've already done that 3 lines above and failed)

    The reason you factor with (b-x) where x is a factor of 15 is because the only way you get 15 at the end is by multiplying (b-x) by some other constant
    (For example, from (b^2 - 3b - 3), 15 has to be -x * -3 otherwise you get a multiple of "b", not a constant)

    Before university, there may be one acceptable solution but I see a=0, b=0, c=0, d=0/0 as an answer too.
     
  11. Azimuth

    Azimuth Chicken Teriyaki Boy!

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  12. Sonicslasher

    Sonicslasher In Law we trust.

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    Divide by zero [​IMG]
     
  13. deathfisaro

    deathfisaro Narcistic Deathfisaro Fan

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    Code got busted there, should have casted to double or float, because mathematically 1 != ((3 * 2) / 2) / 2.

    edit: tried bolding the code, didn't work =P
     
  14. Azimuth

    Azimuth Chicken Teriyaki Boy!

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    yeah, my bad, what a stupid mistake. This is what working in scripting languages does to a person, you start taking these small things for granted [​IMG]
     
  15. Dylan

    Dylan 100 MILES AND RUNNIN'

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    this thread hurts my brain
     
  16. BORTZ

    BORTZ "Another stunning Van Gogh"

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    i tried that before remember?
    [​IMG]
     
  17. Westside

    Westside Sogdiana

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    I also would like to contribute to this wonderful thread:
    - Find the volume of the solid generated by revolving the plane region bounded by the equations :
    y=(1+x^2)^-(1/2) ; y=0; x=1; x=-1
    Revolved around X-axis, using the disc method.
     
  18. Harpuia

    Harpuia GBAtemp Fan

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    I used a calculator and got about 4.935
     
  19. gizmo_gal

    gizmo_gal QWEEN of the RadioActive Force!!!

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    .... [​IMG] Um, ...uh... [​IMG]

    Sorry, I was never any good at algebra... [​IMG]
     
  20. xcalibur

    xcalibur Gbatemp's Chocolate Bear

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    Do you square it before or after you integrate it?
    I always forget when you square y...