Limit at Infinity: Solve Without Squeeze Theorem

mateomy
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Homework Statement



<br /> \lim_{x \to \infty} \sqrt{x}\sin\frac{1}{x}<br />

Homework Equations


I don't think you can use the squeeze theorem here...

The Attempt at a Solution



So I am just studying for an exam that I have tomorrow and I am going through problems that weren't assigned on our homework set, (just in case he wants to slip something in there).

I was looking at the solution to the fore-mentioned limit equation and it references the expansion of sinx. Is this necessary? I've used substitution before in problems like lim as x approaches infinity of xsin(1\x) setting 1\x as y while t approaches zero. Can that sort of thing be done here?THANKS FOR ANY HELP!
 
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To make things clearer:
let t = \frac{1}{x}
an now the limit is
\mathop {\lim }\limits_{t \to 0} \frac{{\sin t}}{{\sqrt t }} = \mathop {\lim (}\limits_{t \to 0} \frac{{\sin t}}{t} \times \sqrt t ).
Now you shall see how to do it.
 
Thank you!
 
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