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Homework Help: Integration by tables, totally confused

  1. Jan 22, 2015 #1
    • Moved from a technical math section, so no template
    I would really appreciate it if people could help with these integrals.
    We are supposed to be doing integrals with this table here:

    Here are the two integrals.
    Technically, I only need one of them completed.
    http://s8.postimg.org/nobr36u51/Screenshot_245.png [Broken]
    http://s10.postimg.org/yl71ys3nt/Screenshot_247.png [Broken]

    I have been working at both of these for over an hour which is not a good idea, but they are just not making sense.

    For one, wolfram alpha isn't even working.
    After doing poly division with (screenshot)247, I've been getting nowhere.

    For 245, I just cannot find a single integral on the whole table to use.
    I would really appreciate a quick solution. An answer would be nice but pointing out EXACTLY which integral in the table is needed for each would be great as well... Especially because I have LITERALLY been working on these for... now 2 hours.
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Jan 22, 2015 #2

    Stephen Tashi

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    [itex] \int{ \frac{-1}{x^2 \sqrt{4x^2 + 9 } } } dx [/itex]
    How did you get logarithms? Did you apply formula 28 ?
  4. Jan 22, 2015 #3
    No, I tried a lot of ones like 62 where they have u terms on the bottom outside of the sqrt.
  5. Jan 22, 2015 #4

    Stephen Tashi

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