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Homework Help: Integration help

  1. Apr 11, 2009 #1
    1. The problem statement, all variables and given/known data
    Can Someone Please Help me integrate the following please...

    2. Relevant equations
    - [tex]\int[/tex] x^11 e^x [tex]/[/tex] 5x^6

    3. The attempt at a solution
    firstly i simplified it to...

    -1/5 [tex]\int[/tex] x^5 e^x [tex]/[/tex] 5

    Then i did integration by parts,
    u = x^5, du = 5x^4, v= e^x, dv= e^x

    So i got,

    -1/5 [ x^5 e^x [tex]\int[/tex] e^x 5x^4 + C

    -1/5 [x^5 e^x - x^5 e^x + C ]

    = -1/5C

    And this seems insanely wrong :(

    Please let me know what I'm doing wrong
  2. jcsd
  3. Apr 11, 2009 #2
    [tex]\int[/tex]5x[tex]^{4}[/tex]e[tex]^{x}[/tex]dx [tex]\neq[/tex] x[tex]^{5}[/tex]e[tex]^{x}[/tex]+C

    You're going to have to use integration by parts a few more times...
  4. Apr 11, 2009 #3
    Is there an easier way to do it? Or is integration by parts the only way?
  5. Apr 11, 2009 #4
    I'd say integration by parts is the best way if not the only way. It will be good practice! Good luck and remember to have fun :)
  6. Apr 11, 2009 #5
    hehe okies thanks!!
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