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6.32.9  Partial fraction expansion: partfrac cpartfrac

The partfrac and cpartfrac commands find the partial fraction expansion of a rational function.


Example.
Find the partial fraction expansion of:

x5−2x3+1
x4−2x3+2x2−2x+1

over the real numbers. Input (in real mode):

partfrac((x^5-2*x^3+1)/(x^4-2*x^3+2*x^2-2*x+1))

Output:

x+2−
1

x−1
+
x−3

x2+1

To find the partial fraction decomposition over the complex numbers, you can either put Xcas in complex mode (see Section 3.5.5) or use cpartfrac.
Input (in complex mode):

partfrac((x^5-2*x^3+1)/(x^4-2*x^3+2*x^2-2*x+1))

or, in real or complex mode:

cpartfrac((x^5-2*x^3+1)/(x^4-2*x^3+2*x^2-2*x+1))

Output:

x+2−
1

x−1
+
−1−2 i

2−2 i

x+i
+
2+i

2−2 i

xi

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