The faces x = 0 and x = c of a slab 0 0. (a) After writing the boundary value problem for the temperatures, make the substitution s = Tx/c to show that u, = (km?/c?)u ,,, u = 0 when s 0 and s = T, and u = f(cs/7) when t= 0. (b) By referring to the solution (5), with coefficients (7), of the problem in Example 1, Sec. 32, write an expression for u in terms of s and t. Then, with the aid of the relation s = Tx/c that was used in part (a), show that n'm?k u(x, 1) = E b, exp sin %3D n=1 where 2 b, dx (n = 1,2,...). %3D