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insane maths problem - help (1 Viewer)

fatmike93

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integrate 1 / ln(tanx) with respect to x

i have no idea how to type this up using comp programs. hop you can understand this and solve it for me.
 

fatmike93

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i have a feeling that its wrong. the line where you sub 'u' in.

you changed it from 1+tanx (sqaured) / tanx to 1+ u (squared) / u.
so you basically let u = tanx as you subbed it in. however, you initially stated that u=ln(tanx). so...

maybe i'm wrong, but just check it. i dont think its that easy otherwise i woulda got it ages ago. LOL i asked my teacher and he subbed it into a maths program today and the program said that the integration was unsolvable.

so you could try it again, but most likely it's unsolvable.

thanks anyway.
 

kcqn93

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i THINK i got it! lol

or not.... silly mistake again!
 
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fatmike93

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well i got it from a friend, who got it from his teacher. his teacher is this insane asian. funniest guy but also insane smart.

most of his questions are from chinese math competitions but they are usually do-able, if you know how to.

but according to the computer program, this question isn't possible. so don't try it. lol

i wasted 2 days of my life trying.
 

Tofuu

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well i got it from a friend, who got it from his teacher. his teacher is this insane asian. funniest guy but also insane smart.

most of his questions are from chinese math competitions but they are usually do-able, if you know how to.

but according to the computer program, this question isn't possible. so don't try it. lol

i wasted 2 days of my life trying.
i typed it in Online Integral Calculator

and it had x/(log (tanx))
 

fatmike93

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i don't really carea about the answer. i really really want to know the method.

but if its definitely doable, then i'll attempt it one last time tomorow.
 

pwoh

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This is using the derivative above



I haven't checked it though


Edit: Nevermind, it doesn't differentiate to give 1/ln(tan x). Damn :( lol
 
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fatmike93

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haha nice try. like i said, it's incredibly hard or impossible to do.

anyways, how do u tyoe the integrals like that? do u have a prgram or do u just use word
 

Tofuu

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haha nice try. like i said, it's incredibly hard or impossible to do.

anyways, how do u tyoe the integrals like that? do u have a prgram or do u just use word
theres a button near the bottom that says launch LaTex equation editor
 

Trebla

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Is it meant to be a definite integral?
 

Trebla

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If it were a neat definite integral, then some properties can be applied that can find the answer without the need to find the primitive.
 

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