Solving Interpolation Error w/ ≤ 5*10-8 Precision

AI Thread Summary
The discussion focuses on determining the step size h for interpolating the function f(x)=cos(x) over the interval [0,π] to ensure that the interpolation error remains within ≤ 5*10-8. The user has calculated the third derivative f'''(x) and established that it is bounded by 1 in the specified interval. They are currently facing challenges in evaluating the expression |(x-xi+1)(x-xi)(x-xi-1)|, which is crucial for estimating the interpolation error. Assistance is requested to progress further in solving the problem. The user expresses gratitude for any help provided.
peripatein
Messages
868
Reaction score
0
Hi,

Homework Statement


Interpolation for the function f(x)=cos(x) for evenly distributed values of x in [0,π] (h=xi+1-xi, xi=ih, i=0,1,...,πh) is carried out. Also known are f(xi).
I am asked to determine the value of h so that the interpolation's error is ≤ 5*10-8.

Homework Equations




The Attempt at a Solution


I have found f'''(x) for x in [0,π] to be ≤ 1.
Now I am stuck with evaluating |(x-xi+1)(x-xi)(x-xi-1)|.
I'd truly appreciate some assistance. Thanks in advance!
 
Physics news on Phys.org
I have managed on my own with this one. Thank you in any case :).
 
Back
Top