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    what is
    y=2/x differentiated
    and y=1/2x differentiated


    is y=2/x -2x^-2
    and y=1/2x -.5x^-2

    are those right?
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    The first one is 2(1/x) and the second is 1/2(1/x) so if you know the derivative of (1/x) then you can just put the constant in front of the derivative to get the answer. Also,

    \displaystyle \frac{1}{x}=x^{-1}

    What's the derivative or x^{-1} ?

    (Both of your answers are wrong)
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    what is this expession simplified
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    but the first one,
    2/x can be written as 2x^-1
    which differentiates to -2x^-2 right?
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    Um, they're both right as far as I can see...

    Yeah they're fine. The other people may be thinking of integration, where 1/x becomes lnx
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    Sorry - I got confused by your first post.

    I thought y=2/x -2x^-2 was your answer but I see now that the '-' was not meant to represent a minus.

    Your first answers were correct.
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    the first is right...the second i think is wrong...it should be -0.5x^2 or -2x^-2

    (Original post by maxfire)
    Um, they're both right as far as I can see...

    Yeah they're fine. The other people may be thinking of integration, where 1/x becomes lnx
    i don't approve of this sig either:hmmm: (if it was you that had the lazytown gif:p:)
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    (Original post by notnek)
    Sorry - I got confused by your first post.

    I thought y=2/x -2x^-2 was your answer but I see now that the '-' was not meant to represent a minus.

    Your first answers were correct.
    the '-' does represent a minus
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    (Original post by someperson)
    the first is right...the second i think is wrong...it should be -0.5x^2 or -2x^-2


    i don't approve of this sig either:hmmm: (if it was you that had the lazytown gif:p:)
    My pedobear sig got removed :emo:
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    (Original post by uxa595)
    what is this expession simplified
    1/x + 1

    ask if you need to know how
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    (Original post by someperson)
    the '-' does represent a minus
    Sorry - I knew that.

    What I meant to say was that I thought (y=2/x -2x^-2) was the whole answer.
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    (Original post by notnek)
    Sorry - I knew that.

    What I meant to say was that I thought (y=2/x -2x^-2) was the whole answer.
    oh ok:p:

    (Original post by maxfire)
    My pedobear sig got removed :emo:
    :awesome:

    but pikachu doesn't drink
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    (Original post by someperson)
    oh ok:p:


    :awesome:

    but pikachu doesn't drink
    Sure he does. Just not on screen obviously. What do you think that'd do for his career?
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    (Original post by maxfire)
    Sure he does. Just not on screen obviously. What do you think that'd do for his career?
    you're wrong...he's innocent:pika:
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    (Original post by someperson)
    you're wrong...he's innocent:pika:
    I used to want a pet pikachu when pokémon first came out.

    Spoiler:
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    I still do :emo:
    Spoiler:
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    I could teach him drinking games
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    im sure this is right for the 2nd Qi wrote
    the Q then in dy form :


    also how would i find x in this:
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    (Original post by uxa595)
    im sure this is right for the 2nd Qi wrote
    the Q then in dy form :
    how did you get that?
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    (Original post by maxfire)
    I used to want a pet pikachu when pokémon first came out.

    Spoiler:
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    I still do :emo:
    Spoiler:
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    I could teach him drinking games
    i still want a pet pikachu:emo:

    Spoiler:
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    i hate you:hmmm:
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    (Original post by uxa595)
    im sure this is right for the 2nd Qi wrote
    the Q then in dy form :
    That's right
    also how would i find x in this:
    Multiply everything by x

    32x^{\frac{3}{2}}-\frac{1}{x}=0

    32x^{\frac{5}{2}}-1=0

    x^{\frac{5}{2}}=\frac{1}{32}

    Solve from there..
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    (Original post by maxfire)
    That's right

    Multiply everything by x

    32x^{\frac{3}{2}}-\frac{1}{x}=0

    32x^{\frac{5}{2}}-1=0

    x^{\frac{5}{2}}=\frac{1}{32}

    Solve from there..
    i'm too slow with latex:sigh:

    and i'm being dumb...but how do you get the first...i get -2 not -1/2
 
 
 
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