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Limit with trigonometric functions

  • Thread starter Jules18
  • Start date
  • #1
102
0

Homework Statement



True or false?

lim Tanx/(1-Cosx) = lim Sec2x/Sinx = Infinity

(limits are as x approaches [tex]\pi[/tex] from the left)

The Attempt at a Solution



I tried just plugging [tex]\pi[/tex] into x in the first limit, and I ended up getting 0/2, which exists but is just 0. So I said false. Am I simplifying it too much? because what I did seems to make sense but it looks like that's not what they wanted me to do.
 
Last edited:

Answers and Replies

  • #2


Isn't it just 0/2=0?
 
  • #3
33,631
5,288


The original limit was neither of the indeterminate forms [0/0] or [infinity/infinity], so L'Hopital's Rule doesn't apply here. Your first approach was correct.
 

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