Solve Improper Integral: $\int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx$

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Archimedes II
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Homework Statement



[itex]\displaystyle \int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx[/itex]

Homework Equations



N/A

The Attempt at a Solution



[itex]\displaystyle \int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx =[/itex]

[itex]\displaystyle lim_{t\rightarrow \infty} \int_{1}^{t} 1/(x^2+ 3 \ |sin x| +2) dx[/itex]

Side Work

[itex]\displaystyle \int 1/(x^2+ 3 \ |sin x| +2) dx[/itex]

I have now clue how to solve this integral. It can't be simplified. U substitution doesn't work nor does a trigonometric substitution. Once I can solve the indefinite itegral I can solve the rest on my own.

Thanks in advance.
 
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Archimedes II said:

Homework Statement



[itex]\displaystyle \int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx[/itex]


Homework Equations



N/A


The Attempt at a Solution



[itex]\displaystyle \int_{1}^{\infty} 1/(x^2+ 3 \ |sin x| +2) dx =[/itex]

[itex]\displaystyle lim_{t\rightarrow \infty} \int_{1}^{t} 1/(x^2+ 3 \ |sin x| +2) dx[/itex]

Side Work

[itex]\displaystyle \int 1/(x^2+ 3 \ |sin x| +2) dx[/itex]

I have now clue how to solve this integral. It can't be simplified. U substitution doesn't work nor does a trigonometric substitution. Once I can solve the indefinite itegral I can solve the rest on my own.

Thanks in advance.

You can't solve the indefinite integral. You just want to prove the improper integral exists. Try a comparison test.
 
Dick said:
You can't solve the indefinite integral. You just want to prove the improper integral exists. Try a comparison test.

Oh ok thanks that makes since now.