What is the Limit of f(x) as x Approaches Infinity?

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Homework Statement



For the following function decide whether f(x) tends to a limit as x tends to infinity. When the limit exists find it.


Homework Equations



f(x)=[xsinx] / [x^2 +1]

The Attempt at a Solution



Im not really sure what method to use for this question.
 
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well sinx cycles from -1 to 1, to infinity and x tends to infinity. What happens to:

x^2+1\;\lim_{x\rightarrow\infty}
 
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x^2 + 1 tends to infinity as x tends to infinity. So infinity over infinity?
 


Actually not exactly as sinx goes from -1 to 1 to the limit of infinity and x goes to infinity so it's between - 1 x infinity and 1 x infinity, infinitely as x approaches infinity. Hehe that makes sense. :smile:
 
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As to my methodology,

<br /> \lim_{x\rightarrow\infty}\frac{xsinx}{x^2+1}

Taking x^2 common, we have the above equation as,
\lim_{x\rightarrow\infty}\frac{x^2(\frac{sinx}{x})}{x^2(1+\frac{1}{x^2})}

Now, cancelling x^2 terms and also we know that \frac{1}{\infty}=~0,

Thus, the function tends to?
(It can't get easier than this.. c'mon..)
 
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