# need help in residual theorm question

• Nov 11th 2009, 03:52 AM
nasir6992
need help in residual theorm question
I need help in solving following Math questions.
Can any one help me in this matter.
Questions are attached as Image file.
• Nov 11th 2009, 04:07 AM
tonio
Quote:

Originally Posted by nasir6992
I need help in solving following Math questions.
Can any one help me in this matter.
Questions are attached as Image file.

Show us what have you done to solve these problems, where are you stuck, etc.

Tonio
• Nov 11th 2009, 04:12 AM
nasir6992
i need you help ....:)
don't know how to solve
• Nov 11th 2009, 04:44 AM
simplependulum
Are you sure those problems are fine at all ?

I am comfused of one of you problems

$\displaystyle \int_0^{\infty} \frac{x^2\ln(x)~dx}{x^2 + a^2}$

I think this integral diverges because $\displaystyle \lim_{x\to\infty} \frac{x^2\ln(x)}{x^2+a^2} \to \infty$
• Nov 11th 2009, 05:01 AM
nasir6992
yes the problems are fine
i need the solution, if u can help
• Nov 11th 2009, 05:20 AM
shawsend
It's an interesting residue problem if it's:

$\displaystyle \int_0^{\infty}\frac{x^2\ln(x)}{(x^2+a^2)^2} dx$
• Nov 11th 2009, 05:30 AM
tonio
Quote:

Originally Posted by nasir6992
i need you help ....:)
don't know how to solve

That's not good enough for me. Your questions look like homework and I won't do it for you. You must have done SOMETHING to solve these problems, and if you haven't then you better begin working.

Tonio
• Nov 11th 2009, 05:44 AM
nasir6992
Thats so kind of you. Can you please guide me or give me any reference to read, to start these problems. That will also be a great help.