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Thread: Solvable?

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    Solvable?

    (x+1)w+3 + (y+1)w+3 = (z+1)w+3

    Find any values for w, x, y, and z for which the above equation is satisfied.


  2. #2
    Frenzied Member Acidic's Avatar
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    using the TI83 solver function:
    if x=1, y=2, z=3 then w=-1.49
    not sure how it does it though.
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    And if I ask for natural numbers?

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    And btw, that's not entirely accurate. If you take all of them on the LHS, you get a difference of -0.010023.

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    So Unbanned DiGiTaIErRoR's Avatar
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    (x^3+3x^2+3x+1)(x+1)^w = -((y+1)^w*(y^3+3y^2+3y+1)-(z+1)^w*(z^3+3z^2+3z+1))

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    So Unbanned DiGiTaIErRoR's Avatar
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    Originally posted by Acidic
    using the TI83 solver function:
    if x=1, y=2, z=3 then w=-1.49
    not sure how it does it though.
    When w = -1.49

    x=(a+b)^.662252 - 1
    y=(-b)^.662252 - 1
    z=(a)^.662252 -1

    a+b >= 0
    a >= 0
    b =< 0

  7. #7
    So Unbanned DiGiTaIErRoR's Avatar
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    w = -1
    x = -(sqr(z^2+2*z-y*(y+2))+1) or
    x = sqr(z^2+2z-y(y+2)) - 1

    w <> 0

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    JFYI, this equation is known as Fermat's Last Theorem.

    The web page shows the original equation.

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    Fanatic Member sql_lall's Avatar
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    Talking hehe

    unfortunately, and very famously, there are no answers to your questions, as you ensure that all bases are >0 and all powers are >2.

    More interesting is more complex qs like this, for example:
    a5+b5+c5=d5+e5

    etc...
    sql_lall

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    Re: hehe

    Originally posted by sql_lall


    More interesting is more complex qs like this, for example:
    a5+b5+c5=d5+e5

    etc...
    a,b,c,d,e = 0


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    So Unbanned DiGiTaIErRoR's Avatar
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    Re: hehe

    Originally posted by sql_lall
    unfortunately, and very famously, there are no answers to your questions, as you ensure that all bases are >0 and all powers are >2.

    More interesting is more complex qs like this, for example:
    a5+b5+c5=d5+e5

    etc...
    a=(e^5+d^5-c^5-b^5)^(1/5)*(-(sqr(5)+1)/4 + sqr(-2*(sqr(5)-5))/4 * i)

  12. #12
    Only Slightly Obsessive jemidiah's Avatar
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    For the original:

    x = y = z = w = infinity

    Now tell me infinity is not a natural number
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  13. #13
    Fanatic Member sql_lall's Avatar
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    Talking hehe

    1) OK. Infinity is not a natural number.
    (Can you count to infinity?) Infact, it isn't a number at all!

    2) As with all these questions, it is looking for NON-TRIVIAL (as in, don't use all 1s or 0s) NATURAL (positive integer) solutions.



    P.S. i believe "NATURAL" includes zero, but defined as positive integer above cos a solution with zero would be trivial.
    sql_lall

  14. #14
    Fanatic Member alkatran's Avatar
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    (x+1)^(w+3) + (y+1)^(w+3) = (z+1)^(w+3)

    x=-1
    y=-1
    z=-1
    w = whatever you want


    this is the sort of problem you're almost better off deciding to simplify (x+1)^(w+3) to 0 in your head... but teachers don't like that very much
    Don't pay attention to this signature, it's contradictory.

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    If the Natural number restriction is not there then the easiest solution is take w=-2

    It will reduce the equation to x+y=z

    And no need to tell much many different solutions U can have now.

    Even if U take w=-3 or w=-1 there are many solution. As in the case of latter it is x^2 + y^2 = z^2

    If the restriction is that w should be >= 0 makes the problem interesting. I will try 2 solve in next 2 days.

    By the way I will say that I am enjoying the company of U all a lot.

  16. #16
    Only Slightly Obsessive jemidiah's Avatar
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    It's, unfortunately, been proven there is no natural number solution to that problem (and others like it). It is a cool equation, nonetheless.
    The time you enjoy wasting is not wasted time.
    Bertrand Russell

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