






PSSOU MA/MSC (Mathematics) Previous Partial Differential Equation (L–293) Solved Assignment 2025
(Assignment—1)
Section—A
1. Auxiliary equation of the linear partial differential equation P Q R p q , are :
(a) P, Q, R dx dy dz
(b) 0 P Q R
dx dy dz
(c) P Q R
dx dy dz
(d) P Q R dx dy dz
2. Partial differential equation formed by eliminating the arbitrary function f from
2 2 ( ) z f x y is :
(a) 0 qy px
(b) 0 xy pq
(c) 0 yp xq
(d) 2 2 z x y
3. Classify the equation 2 2 2
2 2 2 0 u u u
x y z
:
(a) Parabolic
(b) Elliptic
(c) Hyperbolic
(d) None of the above
4. The steady state temperature distribution is governed by :
(a) The Laplace’s equation
(b) The Gauss’s equation
(c) The Green’s equation
(d) None of the above
5. One dimensional wave equation is :
(a)
2 2 2
2 2
u u c
t x
(b) 2 2
2 2 2
1 u u
y c x
(c)
2 2
2 2 2
1 u u
t c x
(d) None of the above
6. D’Alembert’s solution of the wave equation is :
(a) ( , ) ( ) ( ) uxt x ct x ct
(b) ( , ) ( ) ( ) uxt x ct x ct
(c) ( , ) ( ) ( 2 ) uxt x ct x ct
(d) None of the above
7. 2 4
0
(2 3) t e t dt
(a) 6e
(b)
6
2
e
(c)
6
4
e
(d)
6
6
e
8. The solution of Dirichlet’s problem, if exists is :
(a) unique
(b) variable
(c) infinity
(d) None of the above
Section—B
9. Solve :
2 2 p q x y .
10. Solve :
25 40 16 0 r s t .
11. Solve :
sin t xy .
12. Write the three-dimensional heat equation in spherical coordinates.
13. Write one-dimensional wave equation.
14. Write second mean value theorem.