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C3 - check where I have gone wrong pleaseeee :) watch

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    I know this isn't correct as i have the answer, but im not sure where i went wrong/haven't done. Firstly I had to find D/dx (xlnx) which i think is correct. My answer is underlined.

    The second part of the question was to "hence or otherwise" find the intergral. Thanks all

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    You've integrated by parts wrongly. Instead of using \displaystyle \int_b^a uv'\, \mbox{d}x = [uv]_b^a - \int_b^a u'v\, \mbox{d}x you've put u'v' in the second integral. I don't know why the question would say "hence or otherwise", though, since integrating ln x doesn't require you to know how to differentiate xln x.
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    Integral of u.dv = uv - integral of v.du. Check your first line of intergration.
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    thanks all
 
 
 
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Updated: January 17, 2010
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