Vol.1 , No. 5, Publication Date: Jan. 10, 2015, Page: 80-83

[1] | Loc Nguyen, Institute of Mathematics, Hanoi, Vietnam. |

It is very necessary to represent arbitrary function as a polynomial in many situations because polynomial has many valuable properties. Fortunately, any analytic function can be approximated by Taylor polynomial. The higher the degree of Taylor polynomial is, the better the approximation is gained. There is problem that how to achieve optimal approximation with restriction that the degree is not so high because of computation cost. This research proposes a method to estimate feasible degree of Taylor polynomial so that it is likely that Taylor polynomial with degree being equal to or larger than such feasible degree is good approximation of a function in given interval. The feasible degree is called the feasible length of Taylor polynomial. The research also introduces an application that combines Sturm theorem and the method to approximate a function by Taylor polynomial with feasible length in order to count the number of roots of equation in given interval.

Keywords

Taylor Polynomial, Roots of Equation, Analytic Function Approximation, Feasible Length

Reference

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