Use python to solve
For f (x) = x ln(x), (1) use appropriate Lagrange interpolating
polynomial of degree three to approximate f(8.4). Use the following
data: f(8.1) = 16.94410, f(8.3) = 17.56492, f(8.6) = 18.50515,
f(8.7) = 18.82091. (2) use appropriate Newton interpolation
polynomial again to redo the work.