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#2 Re: Help Me ! » integrate » 2009-08-25 01:35:35

Identity wrote:

[hide]
Nevermind this I made a mistake on the first line

anyways atleast u tried..

#3 Re: Help Me ! » integrate » 2009-08-24 23:42:06

hi Ricky!
heyee..i have got the solution for the integral..


but the hint u provided isnt working for the integral

i converted the above expression into the form..
...
n then i applied the form

after then i put tan(x)=t
n then putting all values..ultimately gave me

after that m confused what to do next..

#4 Re: Help Me ! » integrate » 2009-08-24 14:46:14

bobbym wrote:

Can I ask what textbook this came out of ?

actually it came randomly to my mind..i was solving the integral of


n i thought to find the integral that i asked in post #1

#5 Re: Help Me ! » integrate » 2009-08-24 11:16:27

yep i need the steps..

#7 Re: Help Me ! » Limit » 2009-08-05 23:41:52

Ricky wrote:

Unfortunately soroban, the question was to prove that it converges to 0, not just to show convergence.

hmm..well Sorobon ...Ricky is right..anyways...that may help me in some other question big_smile:D

#8 Re: Help Me ! » Limit » 2009-08-05 23:36:20

Ricky wrote:

I think a much easier proof would be to just note that

Note that this is just using the fact that:

And then making this swap for each n, n-1, n-2, ... except for 1.

This shows that

yeah a nice proof..thanks Ricky..

#9 Re: Help Me ! » Limit » 2009-08-05 08:48:41

hi Riad Zaidan!
thanks for the proof..got convinced from that easily..
n juriguen thanks for the link too

#10 Help Me ! » Limit » 2009-08-05 07:01:27

mathkeep
Replies: 12

here is a question of limit...

...where n tends to infinity
actually my limit is coming out to be 0...i thought in this way...
write the limit as :

so the further ratios will make 1 smaller and smaller....thus making the fraction almost zero...
but i want a rigorous proof..

#11 Re: Help Me ! » solve it! » 2009-08-02 02:23:37

hmm..any more replies???
i also think we are done with all the solutions...

#12 Re: Help Me ! » solve it! » 2009-08-02 02:20:02

bobbym wrote:

Hi mathkeep;

Yes, only when n is even. Juriguen has that indicated in post #4.

ok..i did not see that ...thanks for telling ..i think we have got all the solutions now..from post #4...
what do u people say??

#13 Re: Help Me ! » solve it! » 2009-08-02 02:14:32

bobbym wrote:

Hi Juriguen;

Your idea was a lot better than mine so no apology necessary.

Hi mathkeep;

Also for n>3 and odd, x takes imaginary values. For n=3 we have x = 2 π m+(2.35619449... + .881373587... i) m ∈ Z. The complex coefficients do not have a simple form.

nice work but i want real solutions only...

#14 Re: Help Me ! » solve it! » 2009-08-02 02:13:28

Indeed, it would be something like:

But this is not so easy any more!


Jose

yeas u r right now...but as u said this not so easy anymore....
n i have another problem:

when n is odd  x={2k(pi)+1}....

will always be =-1 n
will always be =0...i mean that can be the solution only if n is even.

#15 Re: Help Me ! » solve it! » 2009-08-02 01:53:00

hi juriguen, also m not able to get it..why are u taking n to be a even when the solution is

....cuzat x=
...
and
... i mean it doesnt matter wheher n is even or odd...
correct me if m wrong

#16 Re: Help Me ! » solve it! » 2009-08-02 01:38:08

hi juriguen!
yeah...ur solution seems to be correct but i could not understand this step:


i mean was that an assumption...or what? dizzy

#17 Re: Help Me ! » solve it! » 2009-08-02 01:27:10

hi bobbym..yeah..you r right but what are the other solutions..i was able to make it out..that

is always a solution..n am looking for the method of solving this question too smile

#18 Help Me ! » solve it! » 2009-08-02 01:03:29

mathkeep
Replies: 19

solve the equation:

where n is a given positive integer

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