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Can you help me find this limit: http://screencast.com/t/6CD9ErAG3N9m
All I need is the first step, I am gonna climb from there easily. Sorry if it's a little unclear picture, it's from an old book
 11 months ago
 11 months ago
Can you help me find this limit: http://screencast.com/t/6CD9ErAG3N9m All I need is the first step, I am gonna climb from there easily. Sorry if it's a little unclear picture, it's from an old book
 11 months ago
 11 months ago

This Question is Closed

robz8Best ResponseYou've already chosen the best response.0
for reference, the answer is \[\sqrt3/2\] i do not remember the steps though, sorry
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
I know the answer too my friend, but I dont know how to find it, thanks though
 11 months ago

robz8Best ResponseYou've already chosen the best response.0
sorry i could not help :/
 11 months ago

Stewie_Griffin_Best ResponseYou've already chosen the best response.0
CANT EVEN SEE THE QUESTION
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
How Come?? The guy above you saw it , I posted a picture
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
I can't see it either. what is the limit going to? Can't make it out after the arrow
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
+ infinity ***** I am sorry
 11 months ago

robz8Best ResponseYou've already chosen the best response.0
lim of x going to positive infinity of sin((pi*x)/(23x))
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
\[\lim_{x \rightarrow +\infty}\sin (\frac{ \pi x }{ 23x })\]
 11 months ago

Stewie_Griffin_Best ResponseYou've already chosen the best response.0
can you actually take the pic clearly?
 11 months ago

rajee_samBest ResponseYou've already chosen the best response.1
\[\lim_{x \rightarrow +\infty} Sin (\frac{ \pi x }{ 23x })\]
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
Now Stewie can stop trolling, lol. xD
 11 months ago

rajee_samBest ResponseYou've already chosen the best response.1
I want to learn this too
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
You can divide by the highest power in the denominator which is x
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
But how does that lead you to the solution which is sqrt(3)/2
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
Can't you? \[\large \lim_{x \rightarrow +\infty}\sin(\frac{ \pi x/x }{ \frac{ 2 }{ x }\frac{ 3x }{ x } })\]
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
So what is \[\sin(\frac{ \pi }{ 3 })\]? Whcih quadrant is sine negative ?
 11 months ago

rajee_samBest ResponseYou've already chosen the best response.1
\[\lim_{x \rightarrow +\infty} \sin \frac{ x }{ x }(\frac{ \pi }{ \frac{ 2 }{ x }  3 })\]
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
@myko @timo86m @jim_thompson5910 @jhonyy9 @Hero @Euler271
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
The result is most likely engative yea
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
yes but HOW @rajee_sam
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
Sine is negative in quadrant 3 and 4, so if \[\sin \frac{ \pi }{ 3 } = \frac{ \sqrt{3} }{ 2 }\] then \[\sin \frac{ \pi }{ 3 }= \frac{ \sqrt{3} }{ 2 }\]
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
Am I eligible to differantiate this thing ? because if we differantiate we get sin(pi/3)
 11 months ago

rajee_samBest ResponseYou've already chosen the best response.1
dw:1369516434913:dw
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
You just need to find the positive radian measure, which is \[\frac{ \pi }{ }\] and then translate it accordingly to find which negative value is correlated with the positive radian measure
 11 months ago

rajee_samBest ResponseYou've already chosen the best response.1
\[\sin ( \theta ) =  \sin (\theta)\]
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
sorry,i meant pi/3 *
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
how did you get the x out @rajee_sam
 11 months ago

rajee_samBest ResponseYou've already chosen the best response.1
I am taking a GCF for both numerator and denominator so that I can cancel them out and do not have any x multiplied with anything
 11 months ago

phiBest ResponseYou've already chosen the best response.1
\[\lim_{x \rightarrow +\infty}\sin \left(\frac{ \pi x }{ 23x }\right) = \sin\left( \lim_{x \rightarrow +\infty} \frac{ \pi x }{ 23x }\right)\] as noted above you can rewrite \[ \frac{ \pi x }{ 23x } = \frac{ \pi }{\frac{2}{x} 3} \]
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
Alright! Alright! I solved it this way! By during the time I was trying to solve this I figured out a second way! Tell me if this is correct: Just taking the derivative of both denominator and numerator and then we are done. Can I apply this to ANY limit? Because here it works!
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
that's what i did pi.... :(
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
if you're taking the derivative you'll have to use chain rule on the whole thing, sin (whatever's inside) and then * whatever is inside.
 11 months ago

phiBest ResponseYou've already chosen the best response.1
yes, you can use L'Hopital's rule http://en.wikipedia.org/wiki/L'Hôpital's_rule if you get 0/0 or inf/inf
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
I am talking about this specific problem
 11 months ago

phiBest ResponseYou've already chosen the best response.1
no, use chain rule. use \[ \lim_{x \rightarrow +\infty}\sin \left(\frac{ \pi x }{ 23x }\right) = \sin\left( \lim_{x \rightarrow +\infty} \frac{ \pi x }{ 23x }\right) \]
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
but even if I dont use the chain rule we end up to the same result
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
Ohh so this formula you showed to me just now is only when we have 0/0 or infinite/infinite ?
 11 months ago

JhannybeanBest ResponseYou've already chosen the best response.1
Oh I see, and you'd use LH rule to simplify it further and end up with the same result.
 11 months ago

phiBest ResponseYou've already chosen the best response.1
using L'Hopital's rule needs 0/0 or inf/inf use it on \[ \lim_{x \rightarrow +\infty} \frac{ \pi x }{ 23x } \]
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
ok and I get this http://screencast.com/t/jPlMQFrZ What now?
 11 months ago

phiBest ResponseYou've already chosen the best response.1
you can use L'Hopital d top/ d bottom = pi/3 or you can use algebra
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
and the lim(x>+infinity) goes away?
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
but still I am stuck on the lim thingy
 11 months ago

phiBest ResponseYou've already chosen the best response.1
then sin (pi/3) = sqrt{3}/2 *** and the lim(x>+infinity) goes away? if you use L'Hopital \[ \lim_{x \rightarrow +\infty} \frac{ \pi x }{ 23x } = \lim_{x \rightarrow +\infty} \frac{\pi}{3}= \frac{\pi}{3}\]
 11 months ago

ChristosBest ResponseYou've already chosen the best response.0
I see, thank you all
 11 months ago
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