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## #1 Help Me ! » Laurent Series Expansion » 2013-05-24 20:49:22

clumsy shark
Replies: 1

Expand in Laurent Series :

1-

in the ring :

2-

For  :

MANY THANKS ^_^

## #2 Re: Help Me ! » Fourier representations for tan x » 2013-05-21 22:03:14

^^ It's been a pleasure to know someone dedicated like You  ^_^

## #3 Re: Help Me ! » Fourier representations for tan x » 2013-05-21 21:29:11

No , I'm from Egypt. Do you know it ?

## #4 Re: Help Me ! » Fourier representations for tan x » 2013-05-21 21:07:49

Oh yea then it must be the second

## #5 Re: Help Me ! » Fourier representations for tan x » 2013-05-21 20:30:53

Thank You bobbym ^_^ That was really such an annoying matter, I got it .. THANKS

## #6 Re: Help Me ! » Fourier representations for tan x » 2013-05-21 09:39:45

Thanks bobbym for replying

Well I can't get how he made this expansion ?? Is it allowed ? I see those two answers  contradicting I understand well that tan(x) is unbounded at x = pi/2 and fourier series is only applicable to periodic functions where f (x) is defined for all real x
how could he manage it and what does his phrase 'This series has very poor convergence properties (look at x= pi/4). So the equality
is only in some sense of generalized functions.' means ??
I wanna know what misunderstanding I suffer here

sorry for my bad language
Thnx ^_^

## #7 Help Me ! » Fourier representations for tan x » 2013-05-20 23:26:28

clumsy shark
Replies: 11

Which of fourier representations is suitable for f(x) = tan (x) : fourier trigonometric series, fourier half-range expansion , oe fourier integral and why ?

Well I searched and found that :
1-     tan x cannot be expanded as a Fourier series .Since tan x not satisfies Dirichlets
conditions.(tan x has infinite number of infinite discontinuous).
2- the pic (sorry posting links is not allowed for me )

the first answer is clear for me but I can't understand the pic I go confused :S

## #8 Re: Help Me ! » Electrical Engineering » 2013-05-08 07:44:01

Thank you all for your great Help
sorry if the given is not enough but this what our Dr wrote ,so I'll solve it for DC THANK YOU ALL

## #9 Help Me ! » Electrical Engineering » 2013-05-01 08:22:28

clumsy shark
Replies: 6

calculate form factor

Kindly illustrate

i guess this is DC

Many ThnX ^_^

## #11 Help Me ! » Triple integration » 2012-12-25 00:15:53

clumsy shark
Replies: 2

Given the solid S: z=x^2 + 4y^2 , z <= 16
Find the volume and surface area of the solid S

## #12 Help Me ! » Integration application » 2012-05-29 20:36:05

clumsy shark
Replies: 8

Find the volume generated by revolving the area bounded by Y^2 = X^3 , X=4
about the line X=1
Type y^2 = x^3 , x=4 on wolframalpha to check the area I mean
I can't understand how the area will revolve about a line lying within the area.
Many thanks in advance.:)

## #13 Help Me ! » Analytic Geometry » 2012-05-27 06:37:45

clumsy shark
Replies: 1

In our book of analytic geometry
we have a title The canonical form of a line
it is the equation of a line passing through a point p1(x1 , y1,z1) and parallel to a vector whose Direction Ratio is a:b:c

under another title The Symmetric (Two point) form of a line
is the equation pf line passing through the 2 points p1 (x1, y1, z1) & p2 (c2 , y2 , z2)
so what is the difference between both of them ?? I can figure out the difference between them and the parametric form but those two can't get it ???!! am so confused