USING MATLAB PLEASE

(a) With increment h = 0.1, what is the percent fractional error (compared to the actual derivative) of the second-order-accurate centered finite-difference estimate of the derivative of f(x) = cos(x) at x = 1? (b) Repeat for the derivative estimated by differentiating the interpolat- ing cubic polynomial (using polyfit, polyder, polyval in Matlab) that goes through the function values at x = 0.7,0.9, 1.1, 1.3 (a) With increment h = 0.1, what is the percent fractional error (compared to the actual derivative) of the second-order-accurate centered finite-difference estimate of the derivative of f(x) = cos(x) at x = 1? (b) Repeat for the derivative estimated by differentiating the interpolat- ing cubic polynomial (using polyfit, polyder, polyval in Matlab) that goes through the function values at x = 0.7,0.9, 1.1, 1.3