b]1. The problem statement, all variables and given/known data[/b](adsbygoogle = window.adsbygoogle || []).push({});

F(x) = lim csct - cscx find the value of f '(pi/4) ( f prime pi/4)

t-->x t - x

(the denominator is screwed up. it should be t-->x for the limit and t-x for the denominator, but you guys probably already guess that. )

2. Relevant equations

i dont know. perhaprs first principles. please avoid l'hopitals rule for even i can do that haha. I dont know what im not seeing, i just cant approach the question.

3. The attempt at a solution

iv tried hundreds of things. the first thing i tried was multiplying top and bottom by conjugates to see if i could work out something with that. the second thing i tried was changing csc in to its primitive for 1/sinx and finding a lowest common denominator and using fraction rules. the next thing i tried was separating the top and bottom into functions of their own... that just threw me into a brick wall. please if someone can give me a starting point i would appreciate it soooooo much!

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# Homework Help: Possibly the hardest limit question i have ever come across.

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