How to Integrate \frac{\sqrt{x+1}}{x+3} dx with a Suitable Substitution?

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To integrate the expression ∫(√(x+1)/(x+3)) dx, a suitable substitution is crucial. One effective approach involves first transforming the integrand to simplify the radical, such as letting y = √x. The discussion highlights that using two substitutions can lead to a successful solution. Ultimately, the integration process requires careful manipulation of the terms for clarity. The thread concludes with a successful resolution of the integral using the suggested substitutions.
Ethereal
How does one integrate the following:
By using a suitable substitution, evaluate:
\int \frac{\sqrt{x+1}}{x+3} dx

I tried x=tan^2 \theta, x+1=y, but the whole thing got messier. Anyone knows the correct substitution to make?
 
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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 \frac {\sqrt{x}}{x+2} then let y = \sqrt {x}. It should be apparent what to do next.
 
Thanks for your help. I managed to solve it, required 2 substitutions as you said!
 
Way to go!
 
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