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Find dy/dx when y = x / x^2 + 1 watch

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    Hey,

    For some reason I am unable to know how remove the denominator so if some kind person could go through it with me relatively slowly it would be great

    Find dy / dx where y = x / x² + 1
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    (Original post by supreme)
    Hey,

    For some reason I am unable to know how remove the denominator so if some kind person could go through it with me relatively slowly it would be great

    Find dy / dx where y = x / x² + 1
    x/x²
    = x^1 / x^2
    = x^1 ÷ x^2

    Using the laws of indices
    x^a ÷ x^b = x^(a-b)

    so
    x^1 ÷ x^2
    = x^(1-2)
    =x^(-1)
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    (Original post by supreme)
    Hey,

    For some reason I am unable to know how remove the denominator so if some kind person could go through it with me relatively slowly it would be great

    Find dy / dx where y = x / x² + 1
    y = x / x² + 1

    so x/x² = 1/x (think of it as x/x times x , so one cancels out on top an bottom)

    so y = 1/x + 1

    dy/dx = -1/x²

    does that help?
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    Are you sure its not x/ (x^2 + 1)
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    (Original post by Vazzyb)
    Are you sure its not x/ (x^2 + 1)
    Yes

    (Original post by moojoo)
    y = x / x² + 1

    so x/x² = 1/x (think of it as x/x times x , so one cancels out on top an bottom)

    so y = 1/x + 1

    dy/dx = -1/x²

    does that help?
    Thanks it mostly helps I understand up to y = 1/x + 1, I don't get where the -1 and x² comes from....though..?
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    (Original post by supreme)
    Yes



    Thanks it mostly helps I understand up to y = 1/x + 1, I don't get where the -1 and x² comes from....though..?
    y= x-1 + 1
    when you differentiate x-1 you times x by its power (i.e. -1) and then minus 1 from its original power (i.e. -1-1=-2) to give you its new power so...
    dy/dx= -x-2
    you could also write this as -1/x2
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    (Original post by *bobo*)
    y= x-1 + 1
    when you differentiate x-1 you times x by its power (i.e. -1) and then minus 1 from its original power (i.e. -1-1=-2) to give you its new power so...
    dy/dx= -x-2
    you could also write this as -1/x2
    Thanks I get it now
 
 
 
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