Understanding Limit Denominator Help for \sqrt{x} / CSC x: Approach to PIE

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The discussion revolves around evaluating the limit of \(\sqrt{x} / \csc x\) as \(x\) approaches \(\pi\). Participants clarify that \(\csc x\) is the reciprocal of \(\sin x\) and that substituting \(\pi\) or \(180\) degrees into the equation requires careful handling of units. The confusion arises from attempting to square root \(180\) degrees, which is not a standard operation in this context. It is emphasized that radians should be used instead of degrees in calculus, as they are dimensionless ratios. Ultimately, the limit evaluates to \(0\) when correctly approached using radians.
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Homework Statement


Lim \sqrt{x} / CSC x
x apporoaches PIE





The Attempt at a Solution



heres is what i did I am not sure if its right.

let pie = 180 and csc = 1/sin

the \sqrt{180} / 1 / sin 180

sin of 180 = 0 so that can't be in the denominator

\sqrt{x} * sin 180 / 1

is 0/ 1 = 0

correct or no? i think it is but i also feel like a made a mistake somehwere.
 
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well, why do you feel like you made a mistake?
 
There are a few things that If i was in a bad mood, I was would were extremely incorrect, but right now to me they are funny =] It pi, not PIE lol. And you can't just say, let pi = whatever you want >.<" But remember Cosec is in the denominator! So when you replace is with 1/sin, the whole thing doesn't have a denominator anymore =]
 
what would PI equal then
 
Well pi is equal to pi, approximately 3.1415926535. I know what you were trying to do, change back pi radians into 180 degrees. That works just fine for the sin, no problems there mate. But you can't square root 180 degrees easily can you?
 
good point having the sqrt of 180 deg makes no sense.

puting in 3.141... doest make sense to me either. could you giving me a nudge in the right direction and i will see what i can do from there
 
Ok well there's a special thing about measuring angles in radians instead of degrees. Radians do not have any units, because its really a RATIO. It's a ratio of lengths in a circle, so if we measure with any units, say meters, it becomes a ratio of something meters to something else meters, the units cancel each other out in a sense.

Just remember that in any calculus or limits or the like, radians will be assume and degrees will become a thing of the past. So its quite easy to square root pi, and its also quite easy to find sin pi, or if you like to think of it this way, sin 180 degrees.
 
i got the answer 0 again
 

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