Published online by Cambridge University Press: 08 October 2020
We prove that if f and g are holomorphic functions on an open connected domain, with the same moduli on two intersecting segments, then
$f=g$
up to the multiplication of a unimodular constant, provided the segments make an angle that is an irrational multiple of
$\pi $
. We also prove that if f and g are functions in the Nevanlinna class, and if
$|f|=|g|$
on the unit circle and on a circle inside the unit disc, then
$f=g$
up to the multiplication of a unimodular constant.
The author was supported by the CHED-PhilFrance scholarship from Campus France and the Commission of Higher Education (CHED), Philippines.