(1) Write a function which takes a list of the coefficients of a polynomial P(x) = a0 + a1x + a2x^2 + … + anx^n of arbitrary degree n, and a value of x0, and returns P(x0). You can use the function given in lectures, ensuring you understand how it works.
(2) Use the function to evaluate (a) P1(x) = 4x^4 + 3x^2 + 2 at x = 2. (b) P2(x) = 241x^4 at x = 2. Are these answers exact? Explain why or why not. (Use a print statement to show the evaluation of your function, and answer the question in a comment.)
(3) The power series for the sine function sin(x) is given by sin(x) = Σ (1)^n * (2n+1)! * x^(2n+1) = x – x^3/3! + x^5/5! – x^7/7! + …, for all x. Use the first four terms in this series in the Horner evaluation function at a suitable value of x to give an approximation of sin(π/4).
(4) (a) Use your Horner’s method function to evaluate the polynomial (x-1)^3 at the point x = 1.000001. (b) Is this answer correct? (c) Briefly explain why or why not.
(5) In week 3 we wrote a function to convert from binary to decimal. This can be adapted to other bases; here we will explore octal (base 8). The efficiency of the function we wrote can be improved using the same principle as Horner’s method. Write such a function (horner_octal_to_dec) using the ideas of Horner’s method which takes a list whose entries are integers between 0 and 7, where the list represents a base-8 number, and returns the corresponding decimal integer (so the input [2,5,1] returns the integer 169).