(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I have to find the definite integral with limits of integration of 1 to [tex]\sqrt{3}[/tex] for:

[tex]\int\frac{\sqrt{1+x^2}}{x^2}[/tex]

2. Relevant equations

3. The attempt at a solution

I used trig. sub., so I have:

[tex]x=tan \theta[/tex]

[tex]dx=(sec \theta)^2[/tex]

So:

[tex]=\int\frac{\sqrt{1+(tan \theta)^2}}{(tan\theta)^2}(sec \theta)^2 d\theta[/tex]

[tex]=\int\frac{\sqrt{(sec \theta)^2}}{(tan\theta)^2}(sec \theta)^2 d\theta[/tex]

[tex]=\int\frac{(sec \theta)^3d\theta}{(tan\theta)^2}[/tex]

I can play around with U-sub or Trig. identities but I'm missing something.

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# Homework Help: Trig. Sub. integral

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