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    If i have got 36v.dv/36+v^2 =-g.dx
    and i have to integrate what would i get on the left hand side? Ik i will get -gx+c on the right hand and i will get ln on the left but what goes in front of the ln?
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    (Original post by English-help)
    If i have got 36v.dv/36+v^2 =-g.dx
    and i have to integrate what would i get on the left hand side? Ik i will get -gx+c on the right hand and i will get ln on the left but what goes in front of the ln?
    This is so ambiguous...

    Do you mean \displaystyle \frac{36v}{36+v^2} .dv = -g .dx ??

    In which case, what is the derivative of 36+v^2?? How can you manipulate the numerator to make it equal to that derivative?
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    (Original post by RDKGames)
    This is so ambiguous...

    Do you mean \displaystyle \frac{36v}{36+v^2} .dv = -g .dx ??

    In which case, what is the derivative of 36+v^2?? How can you manipulate the numerator to make it equal to that derivative?
    Yes i mean that!
    The derivative of 36+v^2 is 2v and you have to times by 2 if you take the 36 outside
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    (Original post by English-help)
    Yes i mean that!
    The derivative of 36+v^2 is 2v and you have to times by 2 if you take the 36 outside
    But then you'd have 72v if you do that.

    Just factor out 18.
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    Turn the inside of the integration on the left into f'(x)/f(x), should then know what integrating this makes.
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    (Original post by RDKGames)
    But then you'd have 72v if you do that.

    Just factor out 18.
    Okay ill factor out 18! Yeah ive done it thanks
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    it is best to put modulus lines when you get ln?

    ln |?|

    although in this case 36 + v2 will always be positive.|
 
 
 
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