- #1
sweetvirgogirl
- 116
- 0
Suppose that f is analytic on a domain D, which contains a simple closed curve lambda and the inside of lambda. If |f| is constant on lambda, then either f is constant or f has a zero inside lambda ...
i am supposed to use maximum/modulus principle to prove it ...
here is my take:
if f is constant, i don't see a reason why |f| wouldn't be constant :)
if f is not constant, then the max/min principle applies ...
meaning |f| can not have any local max/min on D
now i am lost at this point ...
i would also like a little clarification on what f is constant on lambda means, because the way i see it .. .if lambda is a closed loop (say a circle), then how can f be always increasing /decreasing ...? maybe i am misinterpreting the problem
i am supposed to use maximum/modulus principle to prove it ...
here is my take:
if f is constant, i don't see a reason why |f| wouldn't be constant :)
if f is not constant, then the max/min principle applies ...
meaning |f| can not have any local max/min on D
now i am lost at this point ...
i would also like a little clarification on what f is constant on lambda means, because the way i see it .. .if lambda is a closed loop (say a circle), then how can f be always increasing /decreasing ...? maybe i am misinterpreting the problem