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  1. #1
    gary1 Guest

    Maths problem

    I'm really stuck on this question, and would be incredibly grateful if anyone could help me:

    ^ = the square root

    ^5 + y = a rational number (ie a number which can be written as a/b)

    can anybody find a value for y?

  2. #2
    MikeNewYork's Avatar
    MikeNewYork is offline VIP Member
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    Re: Maths problem

    Quote Originally Posted by gary1
    I'm really stuck on this question, and would be incredibly grateful if anyone could help me:

    ^ = the square root

    ^5 + y = a rational number (ie a number which can be written as a/b)

    can anybody find a value for y?
    I'm not sure what you are asking. The value of "y" could be just about anything.

  3. #3
    artax Guest

    Re: Maths problem

    [Summing a rational number (y) to an irrational one you always obtain
    an irrational number. So the only way y is rational is that a is equal to b or an his multiple. for example ^5 or 2*^5

  4. #4
    MikeNewYork's Avatar
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    Re: Maths problem

    Quote Originally Posted by artax
    [Summing a rational number (y) to an irrational one you always obtain
    an irrational number. So the only way y is rational is that a is equal to b or an his multiple. for example ^5 or 2*^5
    Erm...OK. :wink:

  5. #5
    Tdol is offline Editor, UsingEnglish.com
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    I was going to say that. <liar>

  6. #6
    MikeNewYork's Avatar
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    Quote Originally Posted by tdol
    I was going to say that. <liar>

  7. #7
    Hong Kong Chinese Guest
    Teacher Tdol,

    You are correct! She/he is a liar!
    One cannot solve an equation with two unknowns!
    e.g. a + b = 10

    if a is equal one, b will be equal to nine,
    However, if a is equal to two, b will be equal to eight and so on.
    In conclusion, a and b are variables.

  8. #8
    RonBee's Avatar
    RonBee is offline Moderator
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    Quote Originally Posted by Hong Kong Chinese
    Teacher Tdol,

    You are correct! She/he is a liar!
    One cannot solve an equation with two unknowns!
    e.g. a + b = 10

    if a is equal one, b will be equal to nine,
    However, if a is equal to two, b will be equal to eight and so on.
    In conclusion, a and b are variables.
    I believe you are right, but I think Tdol was joking by calling himself a liar when he said, "I was going to say that."

    :wink:

  9. #9
    Tdol is offline Editor, UsingEnglish.com
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    Quote Originally Posted by Hong Kong Chinese
    Teacher Tdol,

    You are correct! She/he is a liar!
    One cannot solve an equation with two unknowns!
    e.g. a + b = 10

    if a is equal one, b will be equal to nine,
    However, if a is equal to two, b will be equal to eight and so on.
    In conclusion, a and b are variables.
    Thanks for that, but I was calling myself a liar. If I was right, it was only by accident. If I disagreed with someone's view on the forum,I would try to phrase it more diplomatically.

  10. #10
    MikeNewYork's Avatar
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    Quote Originally Posted by tdol
    Thanks for that, but I was calling myself a liar. If I was right, it was only by accident. If I disagreed with someone's view on the forum,I would try to phrase it more diplomatically.
    I can attest to that fact. :wink:

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