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Homework Help: Quick integration question

  1. Sep 1, 2004 #1
    How does one integrate the following:
    By using a suitable substitution, evaluate:
    [tex]\int \frac{\sqrt{x+1}}{x+3} dx[/tex]

    I tried [tex]x=tan^2 \theta, x+1=y [/tex], but the whole thing got messier. Anyone knows the correct substitution to make?
     
  2. jcsd
  3. Sep 1, 2004 #2

    Tide

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    Here's a start: Do it in stages using the first transformation to get rid of the +1 under the radical so the integrand becomes [itex]\frac {\sqrt{x}}{x+2}[/itex] then let [itex]y = \sqrt {x}[/itex]. It should be apparent what to do next.
     
  4. Sep 2, 2004 #3
    Thanks for your help. I managed to solve it, required 2 substitutions as you said!
     
  5. Sep 2, 2004 #4

    Tide

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    Way to go!
     
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