(*Definethefunction*)f[z_]:=z^3*(1-3*z)/((1+z)*(1+2*z^4))​​​​(*Computetheresidueatz=-Infinity*)​​Residue[f[z],{z,Infinity}]​​​​(*Computetheresidueatz=0*)​​Residue[1/z^2*f[1/z],{z,0}]​​​​
Out[]=
3
2
Out[]=
-
3
2