Medal will be awarded (Calculus)
\[\lim_{x \rightarrow 0}\frac{ 1 }{ x \csc x }\]
Compute the limit
Hey Cimber :) Hmm that name sounds familiar... wasn't that the name of that adorable lil cub from the Lion King?
Let's rewrite cosecant in terms of sine, that should help out quite a bit.
That's Simba but thanks :)
Ooo ya >.<
\[\Large\rm \csc x=\frac{1}{\sin x}\]Remember this one? :d
Yes, but would I flip it then because it would turn to be \[1/1/x sinx?\]
then it would just be x sinx
Careful! :) Only the sin x is getting flipped, ya?\[\Large\rm \lim_{x \rightarrow 0}\frac{ 1 }{ x \csc x }=\quad \lim_{x\to0}\frac{1}{x\left(\frac{1}{\sin x}\right)}\]
You can think of it like this maybe: 1/x * 1/(1/sinx) or like this: 1/(x/sinx)
Why though
\[\Large\rm \frac{1}{x\color{orangered}{\csc x}}=\frac{1}{x\color{orangered}{\left(\frac{1}{\sin x}\right)}}=\frac{1}{\color{orangered}{\left(\frac{x}{\sin x}\right)}}\]The x doesn't go in the bottom bottom with the sinx. Is that the step we're having trouble with?
oooooooooooh
No I'm just having trouble all over because my final exam is next week and it's cumulative
So what is the final answer then??
\[\Large\rm \frac{1}{x\color{orangered}{\csc x}}=\frac{1}{x\color{orangered}{\left(\frac{1}{\sin x}\right)}}=\frac{1}{\color{orangered}{\left(\frac{x}{\sin x}\right)}}=\frac{\sin x}{x}\]So it'll flip like that, ya? :)
And uhh, this is just a limit identity that you're suppose to remember :P\[\Large\rm \lim_{x\to0}\frac{\sin x}{x}=1\]
Ohh I see now. Thank you :)
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