Numerical Method Please solve it with proper steps

Let f(x)=tan(x). In the following we would like to calculate the truncation errors. (a) (3 marks) First write down the approximate polynomial, p3(x), for the function f(x) and identify the Taylor coefficients, a0,,a3. (b) (2 marks) Compute the percentage relative error at x=/4 if f(x) is approximated by p3(x) polynomial. (c) (5 marks) Use the Lagrange reminder form to evaluate the upper bound of truncation error at x=/4 for some [0,/4]