A graduate level question in complex analysis

vijigeeths
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If f and g are two entire functions such that mod(f(z)) <= mod(g(z)) for all z in C, prove that f=cg for some complex constant c.
 
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I tried to prove this by applying Liouville's theorem to f/g.
it is clear that f/g is bounded.
and f/g is analytic except at the zeros of g.
if z1 is a zero of g its a zero of f also.
and if multiplicity of z1 as a zero of g will be less than or equal to multiplicity of z1 as a zero of f.
i got stuck here.
pls help me to prove f/g is analytic at zeros of g also.
so that by Liouville's theorem f/g will be a constant.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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