# Math Help - easy limit problem

1. ## easy limit problem

What is the limit as x-> infinity of arcsec(x)

2. $y = arcsec(x)$ has $x \in [-1,1]$ therefore can it approach infinity?

3. so the limit does not exist?

4. I think not.

5. Originally Posted by IronMan21
What is the limit as x-> infinity of arcsec(x)
domain of $y = arcsec(x) = \arccos\left(\frac{1}{x}\right)$ is $(-\infty,-1] \cup [1, \infty)$

the limit as $x \to \infty$ is $\frac{\pi}{2}$

note the graph ...

6. I was under the impression that

$y = arcsec(x) = \frac{1}{arccos(x)}$

7. I have one more question. If the limit was approaching negative infinity, wouldn't the answer also be pi/2? But that wouldn't make sense right?

8. Originally Posted by IronMan21
I have one more question. If the limit was approaching negative infinity, wouldn't the answer also be pi/2? But that wouldn't make sense right?
look at the graph

9. wow im so stupid thanks