Taylor Series Undefined for n greater than 9

Justin Hughes shared this problem 3 years ago

Running the command TaylorPolynomial[1 / x, 2, 10] returns undefined while TaylorPolynomial[1 / x, 2, n] for 0<n<9 return valid Taylor Polynomials. I do not understand why this would be the case. Have I overlooked something or is there a problem with the command.

Running version 5.0.309.0-3D

Thank you.

Comments (4)


Hi, I confirm.

A workaround : use the CAS with something like

f(x):=TaylorPolynomial[1/x, 2, 10]


I think there is a bug with taylor

In the attached taylor is calculated with CAS

it is also possible a problem of memory . the attached did not work after taylorpolynomial[] out of CAS, but it works after reset GG

Files: foro.ggb

In input bar (without CAS) the tenth derivative for taylor polynomial is computed using chain rule and the result contains (x^2)^2...=x^1024 which gives (numerically) infinity for x=2.

You may either

* use CAS as shown by @mathmagic and @Michel

* use TaylorPolynomial[x^-1, 2, 10]

* wait for 5.0.312 / 6.0.312 that will improve the algorithm used by input bar, solving your particular use case


Thank you all for your quick help. Using CAS works well.

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