Introduction - If you have any usage issues, please Google them yourself
Finds the polynomial p10 of degree less than or equal to 10 that interpolates
cos x on the interval [0, PI/2] at 11 equally spaced points. Study the error betwee
between the function and the polynomial at 41 equally spaced points over the
same interval. Repeat the latter but use your 11 points to be Chebyshevs.