Re: maxima and symbolically finding eigenvalues


"Richard Fateman" <fateman@xxxxxxxxxxxxxxx> wrote in message
news:vZO%f.69707$dW3.16678@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
The eigenvalues of a matrix are the zeros of the characteristic
polynomial.
If the matrix is small enough, you can solve this polynomial even if
it has symbolic coefficients. If the matrix is larger, you may or may
not be able to find a satisfactory way of expressing the eigenvalues
symbolically.

surely then it would only be possible for matrices no larger than 4x4 as
galois showed there cannot exist a formula to solve polynomials of degree
equal to 5 (and greater...?) ?

RJF

"NoIdea" <foru@xxxxxxxxx> wrote in message
news:hOH%f.29800$Ph2.23524@xxxxxxxxxxxxxxxxxxxxxxx
i am using the maxima computer algebra system and noticed that it can
find
eigenvalues symbolically (something which my mathcad program cant
seemingly), and i wonder what algorithm it is using to do this? is it a
variant of divide and conquer?






.

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