Find the temperature u(x, t) in a bar of silver of length 10 cm and constant cross section of area 1 cm² (density 10.6 g/cm³, thermal conductivity 1.04 cal/(cm sec ºC), specific heat 0.056 cal/(g ºC) that is perfectly insulated laterally, with ends kept at temperature 0ºC and initial temperature f(x) ºC, where

f (x) = 4 - 0.8|x - 5|