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dp dp dy dp
y , p (3.13)
dx dy dx dy
y d d dp d 2 p dp dp dy d 2 p dp
2
y ( p) pp p ( ) 2 p
dx dx dy dy 2 dy dy dx dy 2 dy
and etc It is visible from the conducted calculations, that y (k ) is
expressed through derivative functions р(у), the order of which
does not exceed k-1, and also in. As a result we will get
Equation of kind
dp d 2 p d (n ) 1 p
( y , , p , ,..., ) . 0 (3.14)
dy dy 2 dy (n ) 1
If this equation has the common decision
p (y ,c ,c ,...,c ), (3.15)
1 2 n 1
dy
where p , it is enough to separate finding of general
dx
integral variables in the last equation and untie him by
integration:
dy
dx , ,( cy 1 ,c 2 ,...,c n 1 ) x c n . (3.16)
(y ,c ,c ,...,c )
1 2 n 1
If in equation of the considered type of n=2, we come the
offered method at once to equation of the first order:
dp
with F (y , y , y ) 0 we will get y , , p ) , 0 from where
(
dy
the common decision p (y ,c ), and farther
1
dy
dx , ,( cy 1 ) x c 2 .
(y ,c )
1
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