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    How would you integrate x(2x+1)^0.5 using 2x+1 as the substitution (u)?
    I have tried making dx= du/2 and then integrating by writing everything in terms of u but can't get the right answer for some reason...

    RDKGames
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    (Original post by Uni12345678)
    How would you integrate x(2x+1)^0.5 using 2x+1 as the substitution (u)?
    I have tried making dx= du/2 and then integrating by writing everything in terms of u but can't get the right answer for some reason...
    After making the substitution and simplifying you should get:

    \frac{1}{4} \int u^\frac{3}{2} - u^\frac{1}{2} du

    It might be worth posting your working.
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    (Original post by SherlockHolmes)
    After making the substitution and simplifying you should get:

    \frac{1}{4} \int u^\frac{3}{2} - u^\frac{1}{2} du

    It might be worth posting your working.
    Attachment 610444610446

    Sorry went through twice
    Attached Images
      
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    (Original post by Uni12345678)
    ...
    You need to show the working to get to the integral I posted in my first post and not start from there.
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    (Original post by SherlockHolmes)
    You need to show the working to get to the integral I posted in my first post and not start from there.
    But I understand it already, am I doing anything wrong after that??
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    (Original post by Uni12345678)
    But I understand it already, am I doing anything wrong after that??
    Oh ok. The rest of your working is fine. Although, you are missing a constant of integration.
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    (Original post by Uni12345678)
    But I understand it already, am I doing anything wrong after that??
    Forgot the constant of integration.
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    Hahha thank you, but the answers given as 1/15(2x+ 1)^1.5 (3x𝑥 − 1)... +c ofc
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    (Original post by Uni12345678)
    Hahha thank you, but the answers given as 1/15(2x+ 1)^1.5 (3x𝑥 − 1)... +c ofc
    Yeah just get it in a different form. Start by factoring out \frac{1}{15}u^{3/2} and simplify what's inside the bracket.
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    (Original post by RDKGames)
    Yeah just get it in a different form. Start by factoring out \frac{1}{15}u^{3/2} and simplify what's inside the bracket.
    Thank youu
 
 
 
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