partfrac takes as argument a rational fraction.
partfrac returns the partial fraction expansion of this rational
fraction.
The partfrac command is equivalent to the convert command with
parfrac (or partfrac or fullparfrac) as option
(see also 5.22.24).
Example :
Find the partial fraction expansion of :

Input :
^
52*x^
3+1)/(x^
42*x^
3+2*x^
22*x+1))Output in real mode :
^
2+1)) Output in complex mode: