Construct the Lagrange interpolating polynomials for the following functions, and find a bound for the absolute error on the interval [x0, xn].
a. f (x) = e2x cos 3x, x0 = 0, x1 = 0.3, x2 = 0.6, n = 2
b. f (x) = sin(ln x), x0 = 2.0, x1 = 2.4, x2 = 2.6, n = 2
c. f (x) = ln x, x0 = 1, x1 = 1.1, x2 = 1.3, x3 = 1.4, n = 3
d. f (x) = cos x + sin x, x0 = 0, x1 = 0.25, x2 = 0.5, x3 = 1.0, n = 3