Cauchy-Riemann conditions-Multivariable Taylor series

In summary: Sorry, my head has gone to the infinity binomial series. My problem has been solved, thanks you a lot.
  • #1
Batuhan Unal
6
0
İ couldn't understand the last operation, please help me.
 

Attachments

  • YeniBelge 2017-06-14_1.pdf
    756 KB · Views: 256
Physics news on Phys.org
  • #2
Instead of taking the k partial derivatives wrt y, they replace them with ik times k more partial derivatives wrt x as shown in the equation right above.
 
  • #3
Thank you for the answer.
I understood that but then he somehow gets rid of the second ∑ that which the sums with the k and n terms. Actually i i have congested at there.
 
Last edited:
  • #4
Oh. Sorry. I answered the easy part and totally overlooked the hard part. I don't see an answer to that part now.
 
  • #5
Batuhan Unal said:
Thank you for the answer.
I understood that but then he somehow gets rid of the second ∑ that which the sums with the k and n terms. Actually i i have congested at there.

Work out the binomial expansion of ##[(x+iy)-(x_0+iy_0)]^n##. Separate into real and imaginary parts inside the brackets first.
 
  • Like
Likes Batuhan Unal
  • #6
Dick said:
Work out the binomial expansion of ##[(x+iy)-(x_0+iy_0)]^n##. Separate into real and imaginary parts inside the brackets first.
Thank you, now i can see from the n!/(k!(n-k)! terms that how the second sigma notatian has gone. But there i need to do a multivariable binomial series expansion but i can't do it.
 
  • #7
Dick said:
Work out the binomial expansion of ##[(x+iy)-(x_0+iy_0)]^n##. Separate into real and imaginary parts inside the brackets first.
Thank you, now i can see from the n!/(k!(n-k)! terms that how the second sigma notatian has gone. But there i need to do a multivariable binomial series expansion but i can't do it.
 
  • #8
Dick said:
Work out the binomial expansion of ##[(x+iy)-(x_0+iy_0)]^n##. Separate into real and imaginary parts inside the brackets first.
Thank you, now i can see from the n!/(k!(n-k)! terms that how the second sigma notatian has gone. But there i need to do a multivariable binomial series expansion but i can't do it.
 
  • #9
Batuhan Unal said:
Thank you, now i can see from the n!/(k!(n-k)! terms that how the second sigma notatian has gone. But there i need to do a multivariable binomial series expansion but i can't do it.

It's not very clear what you mean. You just want to expand ##(a+b)^n## where ##a=(x-x_0)## and ##b=i(y-y_0)##. It's the perfectly normal type of binomial expansion. Or are you asking about something else?
 
  • Like
Likes Batuhan Unal
  • #10
Dick said:
It's not very clear what you mean. You just want to expand ##(a+b)^n## where ##a=(x-x_0)## and ##b=i(y-y_0)##. It's the perfectly normal type of binomial expansion. Or are you asking about something else?
Sorry, my head has gone to the infinity binomial series. My problem has been solved, thanks you a lot.
 

FAQ: Cauchy-Riemann conditions-Multivariable Taylor series

1. What are the Cauchy-Riemann conditions?

The Cauchy-Riemann conditions are a set of necessary and sufficient conditions for a complex-valued function to be differentiable at a point. They state that the partial derivatives of the real and imaginary parts of the function must satisfy a set of equations, known as the Cauchy-Riemann equations.

2. Why are the Cauchy-Riemann conditions important?

The Cauchy-Riemann conditions are important because they determine when a complex-valued function is differentiable and can be represented by a power series, which is a fundamental concept in complex analysis. They also have applications in physics, engineering, and other fields.

3. What is the Multivariable Taylor series?

The Multivariable Taylor series is a method for approximating a multivariable function using a polynomial. It is an extension of the Taylor series, which is used to approximate single-variable functions. The Multivariable Taylor series takes into account the partial derivatives of the function at a given point, allowing for a more accurate approximation.

4. How are the Cauchy-Riemann conditions related to the Multivariable Taylor series?

The Cauchy-Riemann conditions are necessary for a complex-valued function to be differentiable, and the Multivariable Taylor series requires the function to be differentiable in order to be approximated. Therefore, the Cauchy-Riemann conditions are a crucial component in the derivation and use of the Multivariable Taylor series.

5. What are some practical applications of the Cauchy-Riemann conditions and Multivariable Taylor series?

The Cauchy-Riemann conditions and Multivariable Taylor series have applications in many fields, such as fluid mechanics, electromagnetism, and signal processing. They are used to model and analyze complex systems, as well as to solve differential equations. In addition, they are essential in the development of numerical methods for solving problems in science and engineering.

Similar threads

Back
Top