Let u(x, t) be the solution to utt = 9uxx for 0 ≤ x ≤ 2 and t ≥ 0, where: u(0, t) = 0, u(2, t) = 0, and u(x, 0) = f(x) = 1 − |x − 1|. Use D’Alembert’s solution to find u(1, 0.1) and u(1, 0.8). Be careful to consider that D’Alembert’s solution uses the odd periodic extension of f(x).
5. Find a solution u(x, t) of the following problem utt 0 u(0, t) — и(2, t) — 0 2 sin 3T и(а, 0) — 0, и (х, 0) — sin Tz _
9. Use a suitable Fourier Transform to find the solution of the IVP utt (x, t) Uz(0, t) u(x, t) , uz (z, t) 4uzz (x, t) + q (x, t), 0, t> 0, 0as x → 00, x > 0, t > 0, = = t>0. → = 0, ut (2,0)-( = { t, 0 0-x-2, -1, 0, > 2, u(x, 0) q(a, t) Leave your answer in the form of an integral.
9. Use a suitable Fourier Transform...
4. Consider the semi-infinite string problem given by Utt = cʻuza, 0<x< 0,> 0 u(x,0) = f(x), 0<x< ~ ut(2,0) = g(2), 0 < x < 0 u(0,t) = 0, t> 0 Suppose that c=1, f(0) = (x - 1) - h(2 – 3) and g(C) = 0. (a) Write out the appropriate semi-infinite d'Alembert's solution for this problem and simplify. (b) Plot the solution surface and enough time snapshots to demostrate the dynam- ics of the solution.
1. Let u be a solution of the wave equation u 0. Let the points A, B, C, D be the vertices of the paralleogram formed by the two pairs of characteristic lines r-ctC1,x- ct-2,+ ct- di,r +ct- d2 Show that u (A)+u (C)-u (B) + u (D Use this to find u satisfying For which (x, t) can you determine u (x, t) uniquely this way? 2. Suppose u satisfies the wave equation utt -curr0 in the strip 0...
1. Solve Utt - 4lxx- u(x,0)-ar m(x,0) = 0. b. Now we replace the initial condition in a with u(x,0)-x 1 x e [o,1 0,1 Let ua be the solution of a and let u be the solution of b. Find the set of all x E R such that 14(x, 5) = 11 b(x,5).
1. Solve Utt - 4lxx- u(x,0)-ar m(x,0) = 0. b. Now we replace the initial condition in a with u(x,0)-x 1 x e [o,1 0,1...
9. Consider the beam PDE for the transverse deflection u(x, t) of an elastic beam Utt + Kurz = 0 for 0 < x <L (30) where K > 0 is a constant. Suppose the boundary conditions are given by (31) u(0, t) = uz(0,t) = 0 Uwx (L, t) = Uzzz(L, t) = 0 (32) and the initial conditions are (33) u(x,0) = (x) u1(x,0) = V(x) (34) Use separation of variables to find the general solution to the...
5. Consider the following IBVP (initial boundary value problem utt - Curr = 0, 0<x<1, t>0, with boundary conditions u(0,t) = u(1, t) = 0, > 0 and initial conditions (7,0) = x(1 – 2), 14(2,0) = 0, 0<x< 1. Use separation of variables method to find an infinite series solution of this problem. Do a complete calculation for this problem.
Let f(x) = ſ 1, -1<x< 0 and consider the periodic extension where -2, 0 < x <a f(x++) = f(x). To what value does the Fourier series of f converge when: (a) x = 37/2? (b) x = -27? (a) x (0) (b) X (1)
9. Solve the wave problem: 0 < x < T, t> 0; Utt: t2 0; u(T, t) = 0, u(0, t) = 0, 0 SST. u(x,0) = sin(10r), u(x, 0) = sin(4æ) + 2 sin(6x), Answer: sin(10r) sin(10t). 10 sin(4r) cos(4t) + 2 sin(6x) cos(6t) + u(x, t) =
2. Use separation of variables to solve the IBVP: utt (z, y, t) u(0, y, t) u (x, y,0) uzz(z, y, t) + un, (x, y, t) = 0, 0 < x < 1, 0 < y < 1, 0, u(1,y,t)=0, u(z,0,t)=0, u(z, l,t) = 0 sin(r) sin (2my), ue (r, y,02 sin(2mx) sin(ry) t > 0, = =