How Do You Approximate the Perturbed Root of a Polynomial Function?

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The discussion centers on approximating the perturbed root of the polynomial function defined as f(x) = x^5 - 300x^3 - 126x + 5005, with a known root alpha = 5. The perturbed function is given by F_e(x) = (1 - epsilon)x^5 - 300x^3 - 126x + 5005, where epsilon is a small perturbation. Participants emphasize the need to express the perturbed root alpha(epsilon) in terms of a Taylor series expansion around the known root, leading to the expression alpha(epsilon) = 5 + a epsilon + b epsilon^2 + ... for coefficient determination.

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sprinkle
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Consider the polynomial: f(x)= x^5- 300x^3- 126x+ 5005
which has a root alpha= 5. Also consider the perturbed function
F_e(x)= f(x)- epsilon x^5= (1- epsilon)x^5- 300x^3- 126x+ 5005
where epsilon is a small number. Letting alpha(epsilon) denote the perturbed root of F_e(x)= 0 corresponding to alpha(0)= 5, approximate alpha(epsilon)- 5.

The problem I'm having is that I don't understand what the question is asking.
I tried looking at a few perturbed function question but I can't seem to get it
 
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sprinkle said:
Consider the polynomial: f(x)= x^5- 300x^3- 126x+ 5005
which has a root alpha= 5. Also consider the perturbed function
F_e(x)= f(x)- epsilon x^5= (1- epsilon)x^5- 300x^3- 126x+ 5005
where epsilon is a small number. Letting alpha(epsilon) denote the perturbed root of F_e(x)= 0 corresponding to alpha(0)= 5, approximate alpha(epsilon)- 5.

The problem I'm having is that I don't understand what the question is asking.
I tried looking at a few perturbed function question but I can't seem to get it

5 is not a root of that equation, perhaps it should be f(x)= x^5- 300x^2- 126x+ 5005?
The idea is since the two polynomials are close the roots should be close
take alpha=5+a epsilon+b epsilon^2+...
find the coefficients
 

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