ABSTRACT

I ) + N

),

where

=

1 TCU

) ñ

=

1R

) K ( ó ) E ó ,

= arctan Q

) E ó = F2 + ( Q 2

+ > 22) ;

the Q

are positive roots of the transcendental equation cot( Q F

) = Q 2

Q ( > 1 + > 2) . 3 W . For the solution of the third boundary value problem with nonhomogeneous boundary conditions, see Paragraph 4.1.2-6 with X ( ó , I ) ≡ 0. YZ

4.1.1-8. Domain: 0 ≤ ó ≤ F

. Mixed boundary value problem. 1 W . Longitudinal vibration of an elastic rod with one end rigidly fixed and the other free. The following conditions are prescribed:[

=

( ó ) at I = 0 (initial condition), \ J

= K ( ó ) at I = 0 (initial condition),[ = 0 at ó = 0 (boundary condition),

= 0 at ó = F

(boundary condition). Solution:

( ó , I ) = L M

I ) + N

= ]

(2 ð + 1) 2 F

,

=

0 ñ ( ó ) sin( Q

=

2R

0 K ( ó ) sin( Q

2 W . For the solution of the mixed boundary value problem with nonhomogeneous boundary conditions, see Paragraph 4.1.2-7 with X ( ó , I ) ≡ 0. YZ

4.1.1-9. Goursat problem. The boundary conditions are prescribed to the equation characteristics:[

=

( ó ) for ó − R

I = 0 (0 ≤ ó ≤ ^ ),[ = K ( ó ) for ó +

I = 0 (0 ≤ ó ≤ _ ), where

(0) = K (0). Solution: [

( ó , I ) = ñ G

ó +

2 H − ñ (0). The solution propagation domain is bounded by four lines:

ó −

I = 0, ó +

I = 0, ó −

I = 2 _ , ó +

I = 2 ^ . YZ

4.1.2-1. Domain: − f < ó < f . Cauchy problem. Initial conditions are prescribed: [

= g ( ó ) at I = 0, \ J

= K ( ó ) at I = 0. Solution:

( ó , I ) = 12 [ g ( ó − R

I ) + g ( ó + R

I )] + 12 R h

K ( k ) l k + 12 R

4.1.2-2. Domain: 0 ≤ ó < f . First boundary value problem. The following conditions are prescribed:[

= g ( ó ) at I = 0 (initial condition), \ J

= K ( ó ) at I = 0 (initial condition),[ = o ( I ) at ó = 0 (boundary condition).