Help in MATLAB.

3.2. The degree-n Chebyshev polynomial is defined by These satisfy To(x) -1, Ti(x)- x, and the recursion relation Tn + 1 (x)=2x7, (x)-Tn-1(x), n>1. Write a function chebeval (x, N) that evaluates all of the Chebyshev polynomials of degree less than or equal to N at all of the points in column vector x. The result should be an array of size length (x) by N+1