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arXiv · math/0610549

Quadratic Factors of $f(X)-g(Y)$

Manisha Kulkarni·Peter Müller·B. Sury
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Abstract

We classify the pairs of polynomials $f,g$ over a field $K$, such that $f(X)-g(Y)$ has a factor of total degree at most 2. This was done by Y. Bilu for characteristic 0 fields $K$. As his method does not work in positive characteristic, we use a quite different approach.

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Manisha Kulkarni, Peter Müller, B. Sury. 2006-10-18. Quadratic Factors of $f(X)-g(Y)$. https://doi.org/10.1016/s0019-3577(07)80019-x

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