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and let us integrate:
dy dx dy dx C
, , ln y ln x 1 ln C , y
y x 1 y x 1 x 1
The common decision of LNDE was got. We will search
C x
the common decision of LNDR as y , where xC –
x 1
some function.
C x C x
We will find derivative y
x 1 x 1 2
and we will put y and y in LNDR:
C x C x C x cos x
.
x 1 x 1 2 x 1 2 x 1
We get equation with the separated variables, which after
obvious simplifications acquires a kind
C x cos x ,
from where
~
C x sin x C ,
~
where through C the marked arbitrary became integration.
We will get the common decision of the given equation in a
sin Cx
kind: y .
x 1
2 Method of artificial replacement (Euler-Bernoulli method)
Bernoulli suggested to search the upshots LNDE
y P yx Q x (2.25)
as work of two functions
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