I know that the limit as cos(t) goes to infinity is undefined becuase cosine oscillates between plus and minus one.(adsbygoogle = window.adsbygoogle || []).push({});

Now I have this limit to compute:

Limit of [ (t * cost(t)) / (e^(t)) ] as t goes to infinity

I know that the answer is 0 and I intuitively know why (because exp raises value far quicker than just t)

But, how do I go about proving this...the top is undefined and using LoHospitals rule gets no where becuase a (t * sin(t)) will still be in the numerator.

So how do I go about doing this? Can I just ignore the affects of the cos and just use LoHospitals rule for t/e^t??

Thanks for any help

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# Homework Help: A Limit

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