Специальные функции. Мицик М.Ф. - 7 стр.

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     
 ,   
.
.

( )
,xaxaxxy
m m
m
m
m
m
∑∑
=
=
+
==
0 0
σσ
(16)

,...,...,,,
10 m
aaaσ
,     , 
( )
xy
 (7).
 (16) 
( )
xy

( )
xy
,  (7):
( )( ) ( )
0
1
0
2
0
2
00
=+
+++++
=
+
=
++
=
+
=
+
m
m
m
m
m
m
m
m
m
m
m
m
xaxa
xamxamm
σσ
σσ
ν
σσσ
:
( )
( )
( )
( )
[ ]
{ }
=
+
+
=+++
+++
0
2
2
2
1
1
2
2
0
22
.0
1
m
m
mm
xaam
xaxa
σ
σσ
νσ
νσνσ
  
,...3,2,,,
1
=
++
mxxx
mσσσ
 
:
( )
,0
0
22
= aνσ
(17)
( )
,01
1
2
2
=+ aνσ
(18)
( )
(
)
...,3,2,0
2
2
2
==++
maam
mm
νσ
(19)
      (7), 
,0
0
a

ν
σ ±=
. 
ν
σ
=
. 
(18) , 
,0
1
=a
 (19) :
( )
...,3,2,
2
2
=
+
=
m
mm
a
a
m
m
ν
(20)

...,2,1,12
=
+
=
kkm
 , 
,0
1
=a
 (20) ,
:
...,2,1,0
12
==
+
ka
k
(21)
                                                                                 ,
                                                                                                 .

                                                                                                                      .


                                           ∞                                 ∞
                  y( x ) = x          σ
                                          ∑a           m   x = ∑ am x m+σ ,
                                                               m
                                                                                                                                                (16)
                                          m =0                              m=0

       σ , a0 , a1 ,..., am ,... −                                 ,                                                                            ,
y( x )                                                                               (7).
                                  (16)                                           y′(x)                   y′′(x ) ,                       (7):
           ∞                                                                              ∞

          ∑ (m + σ )(m + σ − 1)a
          m=0
                                                                   m   x   m+σ
                                                                                 +∑ (m + σ ) am x m+σ +
                                                                                         m=0
                       ∞                                   ∞
                 + ∑ am x             m+σ +2
                                                   − ∑ν 2 am x m+σ = 0
                      m=0                              m=0
                                                                                     :
                  (σ   2
                                      )
                           −ν 2 a0 xσ + (σ + 1) −ν 2 a1 xσ +1 +(                 2
                                                                                               )
                             {[                                        ]                        }x
                       ∞
                  + ∑ (m + σ ) −ν 2 am + am−2                                                            m+σ
                                                                                                               = 0.
                                                   2

                      m =0

                                                                                      xσ , xσ +1 , xσ +m , m = 2,3,...
                              :
                  (σ   2
                                      )
                            −ν 2 a0 = 0 ,                                                                                                       (17)
                  ((σ + 1) −ν ) a = 0 ,
                                  2            2
                                                                                                                                                (18)
                   ((m + σ ) −ν ) a + a
                                                           1

                                                                                         = 0 , m = 2, 3, ...
                                      2            2
                                                               m            m−2                                                                 (19)
                                                                                                                                 (7),      a0 ≠ 0 ,
                            σ = ±ν .                                                                                      σ =ν .
(18)              ,          a1 = 0 ,                                                     (19)                               :
                                              am − 2
                              am =                     , m = 2, 3, ...
                                            m(m + 2ν )
                                                                                                                                                (20)

               m = 2k + 1, k = 1, 2, ...                                                             ,           a1 = 0 ,         (20)                 ,
                                                                                                          :
                              a2 k +1 = 0 , k = 1, 2, ...                                                                                       (21)