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    Can someone help me factorise this please confused


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    (Original post by Abby5001)
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    Can someone help me factorise this please confused


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    I mean no offence by this, but perhaps it would be a good idea for you to practice factorising complicated things, as that seems to be where you're having trouble rather than stuff to do with the product rule / differentiation.

    But similar to previous threads, if you set u = (2x+1) and rewrite everything you may be able to see how to factorise it more clearly.

    Or even better .. (2x+1)^1/2 but without substituting the x as it's more simple that way.
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    (Original post by SeanFM)
    I mean no offence by this, but perhaps it would be a good idea for you to practice factorising complicated things, as that seems to be where you're having trouble rather than stuff to do with the product rule / differentiation.

    But similar to previous threads, if you set u = (2x+1) and rewrite everything you may be able to see how to factorise it more clearly.
    I've done that and it's no clearer to me


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    (Original post by SeanFM)
    I mean no offence by this, but perhaps it would be a good idea for you to practice factorising complicated things, as that seems to be where you're having trouble rather than stuff to do with the product rule / differentiation.

    But similar to previous threads, if you set u = (2x+1) and rewrite everything you may be able to see how to factorise it more clearly.
    Doesn't matter I understand now


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    (Original post by Abby5001)
    I've done that and it's no clearer to me


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    Okey dokey, no worries

    Kind of cheating here by leaving the x as it is in a substitution, but that'd just make it more confusing.

    If u = (2x+1)^(1/2)

    Then  \frac{dy}{dx} = 3x u^{-1} + 3u

    And if you factor out u^-1 from both terms, using that u = u^2 * u^-1 you get 3u^-1 (x + u^2) and then put things back in.

    I may have mislead you by suggesting u = 2x+1 rather than (2x+1)^(1/2), sorry!
 
 
 
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