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since

y

0

(

x

)

y

IV

(

x

) =

p

0

|

y

|

k

1

y

(

x

)

y

0

(

x

)

<

0

on

x

000

j

, x

0

j

and

y

0

(

x

0

j

) =

=

y

000

(

x

000

j

) = 0

.

The rest ones follow from

y

00

(

x

)

y

000

(

x

)

>

0

on

x

0

j

, x

000

j

+1

.

Finally, for the first of (12) we have

y

000

(

x

j

)

2

y

000

(

x

00

j

+1

)

2

=

2

x

00

j

+1

Z

x

j

y

000

(

x

)

y

IV

(

x

)

dx

=

= 2

p

0

x

00

j

+1

Z

x

j

y

000

(

x

)

y

(

x

)

|

y

(

x

)

|

k

1

dx

=2

p

0

y

00

(

x

)

y

(

x

)

|

y

(

x

)

|

k

1

x

00

j

+1

x

j

2

kp

0

Z

x

00

j

+1

x

j

y

00

(

x

)

y

0

(

x

)

|

y

(

x

)

|

k

1

dx <

0

,

since

y

0

(

x

)

y

00

(

x

)

>

0

on

x

j

, x

00

j

+1

and

y

(

x

j

) =

y

00

(

x

00

j

+1

) = 0

,

whereas the

rest inequalities follow from

y

000

(

x

)

y

IV

(

x

)

>

0

on

x

00

j

+1

, x

j

+1

.

I

So, the absolute values of the local extrema of any typical solution to

equation (1) form a strictly increasing sequence. The same holds for its

first, second, and third derivatives.

Hereafter we need some extra notations. Put

Ω

1

+

=Traj

1

+

S

3

,

1)

S

3

.

This is a compact subset of the interior of

Ω

+

containing ultimate parts

of all trajectories generated by maximally extended typical solutions to

equation (1) with

p

0

= 1

.

As for solutions generating the curves in

R

4

completely lying in

Ω

+

,

the trajectories related completely lie in

Ω

1

+

.

Besides, we define the compact sets

K

i

=

a

Ω

1

+

:

a

i

= 0

and the

functions

ξ

j

:

R

4

\{

0

} →

R

,

j

= 0

,

1

,

2

,

3

,

taking each

a

R

4

\{

0

}

to the

minimal positive zero of the derivative

y

(

j

)

(

x

)

of the solution to the initial

data problem

y

IV

(

x

) +

y

(

x

)

|

y

(

x

)

|

k

1

= 0;

y

(

j

)

(0) =

a

j

,

j

= 0

,

1

,

2

,

3

.

(13)

Further, to each solution

y

(

x

)

to equation (1) we associate the function

F

y

(

x

) =

3

X

j

=0

ρy

(

j

)

(

x

)

1

j

(

k

1)+4

with

ρ

=

p

1

k

1

0

.

The notation

F

y

does not

use

p

0

,

since non-trivial functions cannot be solutions to equation (1) with

different

p

0

.

Lemma 7.

The restrictions

ξ

i

|

K

j

, i, j

= 0

,

1

,

2

,

3

,

are continuous.

J

First we prove continuity of

ξ

i

at

a

Ω

+

with

a

i

>

0

.

Suppose

ξ

i

(

a

) =

x

i

and

ε >

0

.

We can assume that

ε

is sufficiently small to be less than

x

i

and to

provide, for the solution

y

(

x

)

to (13), the inequalities

y

(

i

)

(

x

ε

)

>

0

on

[0

, x

i

ε

]

and

y

(

i

)

(

x

i

+

ε

)

<

0

.

In this case the point

a

has a neighborhood

14

ISSN 1812-3368. Вестник МГТУ им. Н.Э. Баумана. Сер. “Естественные науки”. 2015. № 2