PHYSICS · Multi-part · Fermi University Physics · Mathematical Methods for Physics · Numerical and computational mathematics · Numerical and computational mathematics
Error, Chance and the Machine, Ch Approximating a function: interpolation and differentiation
Problem
A radioactive source has count rate R(t)=R0e−t/τ with R0=1000s−1 and τ=5.0s. A degree-4 polynomial model of R on t∈[0,10]s is to be built from samples at the five Chebyshev points of the second kind, mapped from [−1,1] to [0,10] by tj=5+5cos(jπ/4), j=0,1,2,3,4.
((a)) Compute the five nodes tj, to two decimal places.
((b)) Compute R(tj) at each node, to three significant figures.