1, 2,..., n (8), (7) ( ). (7) , . , (14) (15), . .
(7)
= 1() 1 + 2() 2 +... + n () n,
1, 2,..., n (8), 1(), 2(),..., n () :
|
(17) , .. , W (x) ¹ 0 (. 2.2).
1.
y ' + x ∙ y ''= x 2. (18)
. . .
1.
x ∙ y '' + y ' = 0. (19)
, . y ' = z, , y '' = z, (19)
x ∙ z ' + z = 0.
. :
Þ Þ Þ .
, : . :
Þ Þ
(19). , , , 2 = 1 (19).
2. (18) :
. (20)
1(), 2() :
(21)
, (18) ¹ 0,
. (22)
f (x) = , , 2 = 1 (21) :
Þ
(20) , :
;
.
y ', y '' (22),
.
Þ Þ .
(21) .
, .
, 1() , 2() (20), (18):
,
1, 2 .
, = 0 (18) y ' = 0. : = .
|
|
2.
.
. . .
1.
.
.
.
k 1= 1, k 2= 1, k 3= 2 (. 2.3, 1). ,
= 1 x + C 2 - + C 3 2.
, , 1 = , 2 = -, 3 = 2 .
2.
= 1() x + C 2() + C 3() 2. (23)
1(), 2(), 3() (17).
Þ
Þ
, , :
, , .
, :
;
;
.
, 1(), 2(), 3() (23), :
= x + - + 2 =
= 1 x + C 2 - + C 3 2 + ,
1, 2, 3 .