# How to specify - Differential equation initial conditions

Posted 8 years ago
8899 Views
|
2 Replies
|
2 Total Likes
|
 I have inputted the following differential equation into Wolfram Alpha:d^2y/dx^2+3dy/dx+2y=e^tI am struggling to work out how specify that y=1 and dy/dx=0 at t=0, so that I can find the particular solution. Any help would be greatly appreciated!
2 Replies
Sort By:
Posted 8 years ago
 The conditions are evidently incomplete: In:= DSolve[{D[y[x, t], {x, 2}] + 3 D[y[x, t], x] + 2 y[x, t] == E^t, y[x, 0] == 1, D[y[x, 0], x] == 0}, y[x, t], {x, t}] During evaluation of In:= DSolve::bvnr: For some branches of the general solution, the given boundary conditions do not restrict the existing freedom in the general solution. >> During evaluation of In:= DSolve::bvsing: Unable to resolve some of the arbitrary constants in the general solution using the given boundary conditions. It is possible that some of the conditions have been specified at a singular point for the equation. >> Out= {{y[x, t] -> 1/2 E^(-2 x) (E^(t + 2 x) + 2 C[t] + 2 E^x C[t])}} 
Posted 8 years ago