a) Find your answer by using a forward difference to approximate the derivative of f(x) = cos(x) at x = by using different step sizes as follows: [Please use 8 decimal points for your calculation.] i) h = 0.1 ii) h=0.01 iii) h = 0.001 iv) h = 0.0001 b) Given the exact value for the differentiation of f(x) = cos(x) is -0.86602540. Compare all of the results that you get in a). c) Central difference formula has been known to provide more accuracy in approximation. By using this information, identify the new result of the approximation by using the best step size that you have concluded in b) and write new conclusion.