Calculate the five Chebyshev nodes in the interval [-1,1] which are used when interpolating with a degree four polynomial. Evaluate the function f(x)=2arcsin(x) at each of these points. Construct the degree four Chebyshev polynomial. Evaluate the resulting polynomial at x=0.8 and compare with the actual value of the function.
The solution demonstrates how to interpolate a function using Chebyshev polynomials.