Editing Partial fraction decomposition (section)

===Polynomial part===
There exist two polynomials {{mvar|E}} and {{math|''F''{{sub|1}}}} such that 
<math display="block">\frac FG=E+\frac{F_1}G,</math>
and
<math display="block">\deg F_1 <\deg G,</math>
where <math>\deg P</math> denotes the [[degree of a polynomial|degree]] of the polynomial {{mvar|P}}.

This results immediately from the [[Euclidean division of polynomials|Euclidean division]]  of {{mvar|F}} by {{mvar|G}}, which asserts the existence of {{mvar|E}} and {{math|''F''{{sub|1}}}} such that <math>F = EG + F_1</math> and <math>\deg F_1 < \deg G.</math>

This allows supposing in the next steps that <math>\deg F <\deg G.</math>