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    THANKS for your help guys
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    Try multiplying both sides by e^(-x) and simplifying
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    (Original post by Edgemaster)
    Try multiplying both sides by e^(-x) and simplifying

    I've got to ye^-x=1+e^-2x
    Now what
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    (Original post by mariejuana)
    y=e^x +e^-x
    express in terms of y
    No idea.
    I've taken logs and all that stuff but I can't really find a way how to do it
    This is possible but it's an odd question. Have you posted the question exactly as you see it? Is this working as part of a larger question?
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    (Original post by Notnek)
    This is possible but it's an odd question. Have you posted the question exactly as you see it? Is this working as part of a larger question?
    exact question=
    given that y=e^x +e^-x
    express X in terms of Y
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    (Original post by mariejuana)
    I've got to ye^-x=1+e^-2x
    Now what
    Honestly I'm not sure, I just remember seeing something similar and that multiplying by e^-x made it easier
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    (Original post by mariejuana)
    exact question=
    given that y=e^x +e^-x
    express X in terms of Y
    Where did you get this question from?

    If you let X = e^x then you have

    y = X + 1/X

    See if you can make X the subject of this.
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    (Original post by Notnek)
    Where did you get this question from?

    If you let X = e^x then you have

    y = X + 1/X

    See if you can make X the subject of this.
    I'm currently doing as maths and this one of many questions from our half term homework assessment.
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    (Original post by Notnek)
    Where did you get this question from?

    If you let X = e^x then you have

    y = X + 1/X

    See if you can make X the subject of this.
    Ican't xD
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    (Original post by mariejuana)
    Ican't xD
    Please always post what you've tried.

    y = X + 1/X

    If instead of y you had e.g. 2 it would be

    2 = X + 1/x

    and you can rearrange this into a quadratic and solve. Try doing the same thing but for y instead of 2. Post your working if you get stuck.

    By the way, you wouldn't see this question in a textbook or exam so I assume your teacher made it up? Are you doing A Level maths?
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    (Original post by Edgemaster)
    I haven't double checked this but I think it makes sense
    Please don't post full solutions.
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    (Original post by Notnek)
    Please don't post full solutions.
    Sorry, I forgot
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    (Original post by Notnek)
    Please don't post full solutions.
    Had the answer on wolfraam anyway xD
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    (Original post by mariejuana)
    Had the answer on wolfraam anyway xD
    Why did you ask for help then?
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    (Original post by Notnek)
    Why did you ask for help then?
    to see how to get to the answer
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    (Original post by mariejuana)
    to see how to get to the answer
    Oh I thought you meant you had the full working on Wolfram Alpha.
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    (Original post by Notnek)
    Oh I thought you meant you had the full working on Wolfram Alpha.
    Could you possibly delete this thread now xD?
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    (Original post by mariejuana)
    Could you possibly delete this thread now xD?
    I can't remove threads. Any reason why you want it deleted? Any question in the maths forum could be useful in the future for students who have the same question.
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    (Original post by Notnek)
    I can't remove threads. Any reason why you want it deleted? Any question in the maths forum could be useful in the future for students who have the same question.
    Don't want people to laugh at how stupid I am xD
    all MY THREADS are me literally asking for help in maths
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    (Original post by mariejuana)
    Don't want people to laugh at how stupid I am xD
    all MY THREADS are me literally asking for help in maths
    But this was a tough question so no one is going to laugh at you. I bet the majority of A Level students couldn't do it.

    For this reason it would be useful to keep it in the maths forum

    (although I see you removed the original question).
 
 
 
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