Prove No Analytic Function F on Annulus D: 1<|z|<2

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SUMMARY

The discussion centers on proving the non-existence of an analytic function F on the annulus D: 1<|z|<2 that satisfies the condition F'(z) = 1/z for all z in D. The approach involves assuming the existence of F and deriving that F(z) must equal Log z + c, given that the derivative of Log z is 1/z. The key conclusion is that a path C can be found such that the integral ∫_C (1/z) dz is non-zero, leading to a contradiction.

PREREQUISITES
  • Complex analysis, specifically the properties of analytic functions
  • Understanding of logarithmic functions in complex variables
  • Knowledge of contour integration and path independence
  • Familiarity with the concept of annuli in the complex plane
NEXT STEPS
  • Study the properties of analytic functions in complex analysis
  • Learn about contour integration techniques and their applications
  • Explore the implications of the logarithmic function in complex variables
  • Investigate the concept of path independence in integrals over analytic functions
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Students and researchers in complex analysis, mathematicians focusing on analytic functions, and anyone interested in the properties of integrals in the complex plane.

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Homework Statement


Prove that there does not exist an analytic function on the annulus D: 1<|z|<2, s.t. F'(z) = 1/z for all z in D.


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The Attempt at a Solution


Assume F exists, then for z in D, not a negative number, F(z) = Log z + c since Log' z = 1/z... Lost
 
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