Introduction 9
Exercises 1.2
Find the general solution of each PDE. The solutionuis a function of the
variables which appear, unless otherwise stated.
1.uy=2x
2.ux=sinx+cosy
3.ux=sinx+cosy,u=u(x, y, z)
4.uyy=x^2 y
5.uxy=x−y
6.uxxy=0
7.uxxyy= sin 2x
8.uxzz=x−yz+y^3
9.uxyzz=0
10.uxyyzz=xyz
11.uy− 4 u=0,u=u(x, y)
12.ux+3u=ex,u=u(x, y)
13.ux−y^2 u=0
14.ux+3u=xy^2 +y
15.uy+xu=2
16.ux−zu=y−z
17.uxx+ux− 2 u=0,u=u(x, y)
- Find all solutions of the PDEuy=2xwhich also satisfy the additional
requirement that
a)u(x,0) = sinx
b) u(x,3) = sinx
c) u(0,y)=3y
- Find all solutionsu(x, y)ofthePDEux− 2 u= 0 which also satisfy the
additional requirement that
a)u(0,y)=y^2
b) u(1,y)=y^2
c) u(x,1) =x^2