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posted by  hpKeeper on 10/20/2009 7:16:11 PM  |  status: Closed  |  Earned Karma: 0

limit, lhospital rule.

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N/A N/A N/A N/A 10/20/2009 at 11:00:00 PM
Question Details:
\lim_{ x \rightarrow \frac{\pi}{2} } 5 \cos(3 x) \sec (-7 x)
(5 (-1 + 2 Cos[2 x]))/(-1 + 2 Cos[2 x] - 2 Cos[4 x] + 2 Cos[6 x])?
Tags: Calculus

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Oracle
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posted by Grace on 10/20/2009 7:32:40 PM  |  status: Live
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Response Details:
You actually have to get a value at the end since you want to evaluate the limit.

Rewrite:


Plugging in now gives you the indeterminate form 0/0 so you can apply L'hospital's rule:



Plugging in now gives you:



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