Consider an elastic string of length L whose ends are held fixed. The string is set in motion with no initial velocity from an initial position u(x, 0) = f(x). Let L = 10 and a = 1 in parts (b) and (c). (A computer algebra system is recommended.) f(x) = 2x L , 0 ≤ x ≤ L 2 , 2(L − x) L , L 2 < x ≤ L (a) Find the displacement u(x, t) for the given initial position f(x). (Use a to represent an arbitrary constant.) u(x, t) = [infinity] n = 1 (b) Plot u(x, t) versus x for 0 ≤ x ≤ 10 and for several values of t between t = 0 and t = 10.