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    integrate 1/(u+1)^2

    I already replaced what was inside with u and am now integrating it with respect to du.

    I thought you would usually move the bracket to the numerator and take out what is in the brackets, but because ive already done that, how do I integrate it and why dont I repeat the step of taking out what is in the brackets?
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    (Original post by Maths&physics)
    integrate 1/(u+1)^2

    I already replaced what was inside with u and am now integrating it with respect to du.

    I thought would usually move the bracket to the numerator and take out what is in the brackets, but because ive already done that, how do I integrate it and why dont I repeat the step of taking out what is in the brackets?
    Note this expression is just (u+1)^(-2) which you should just know how to integrate
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    I hate this part of C4, it's a pain. I don't get the whole Ln part of substitution
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    (Original post by B_9710)
    Note this expression is just (u+1)^(-2) which you should just know how to integrate
    yes, thats what I said (id move the bracket to the numerator). however, at that point id take out u+1 from inside the brackets and differentiate it. but ive already done that - hence why its a u inside.
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    (Original post by Maths&physics)
    yes, thats what I said (id move the bracket to the numerator). however, at that point id take out u+1 from inside the brackets and differentiate it. but ive already done that - hence why its a u inside.
    Why are you differentiating though, what's your logic for doing that?
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    (Original post by B_9710)
    Why are you differentiating though, what's your logic for doing that?
    you usually take out whats inside the bracket
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    (Original post by Maths&physics)
    you usually take out whats inside the bracket
    I'm not sure I understand what you mean
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    (Original post by B_9710)
    I'm not sure I understand what you mean
    its ok, I did it my way and I got it right.
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    (Original post by Maths&physics)
    you usually take out whats inside the bracket
    I don't think that warrants as an answer to his question whatsoever, but OK. I *think* what you're referring to is integration by substitution, whereby here you would 'take out' v=u+1 and differentiate it to get dv=du. Needless step TBH, but you end up with

    \displaystyle \int v^{-2} .dv

    Would help if you construct your questions clearly and coherently.
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    (Original post by RDKGames)
    I don't think that warrants as an answer to his question whatsoever, but OK. I *think* what you're referring to is integration by substitution, whereby here you would 'take out' v=u+1 and differentiate it to get dv=du. Needless step TBH, but you end up with

    \displaystyle \int v^{-2} .dv

    Would help if you construct your questions clearly and coherently.
    thats exactly would I would do (substitution). thanks
 
 
 

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