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its neighboring points of local extremum,

x

0

j

and

x

0

j

+1

,

ultimately satisfies

the estimates

m

(

x

0

j

+1

x

0

j

)

F

y

(

x

0

j

)

k

1

M.

(16)

J

Put

E

+

= Φ

E

Ω

1

+

.

It is a compact subset of the set

E

defined

by (6) and lying inside

Ω

+

. Put

m

= inf

{

ξ

1

(

a

) :

a

E

+

, a

1

= 0

}

>

0;

M

= sup

{

ξ

1

(

a

) :

a

E

+

, a

1

= 0

}

<

.

Let

y

(

x

)

be a typical solution to equation (1),

x

0

j

and

x

0

j

+1

be

neighboring points of its local extremum. We can choose positive constants

A

and

B

such that the function

z

(

x

) =

Ay

(

Bx

+

x

0

j

)

is a solution to equation

(1) with

p

0

= 1

and its data at zero correspond to some point in

E,

i.e.

F

z

(0) = 1

.

It is sufficient for this to find a positive solution to the system

A

k

1

=

B

4

p

0

;

3

X

m

=0

AB

m

y

(

m

)

(

x

0

j

)

1

m

(

k

1)+4

= 1

,

namely

A

=

 

3

X

m

=0

y

(

m

)

(

x

0

j

)

p

m

4

0

1

m

(

k

1)+4

 

4

;

B

=

3

X

m

=0

ρy

(

m

)

(

x

0

j

)

1

m

(

k

1)+4

!

(

k

1)

=

F

y

(

x

j

)

(

k

1)

.

Moreover, for local extrema with sufficiently large numbers, the point

defined in

R

4

by the data of the function

z

(

x

)

at zero belongs to

E

+

.

Hence

the first positive point L of local extremum of

z

(

x

)

belongs to

[

m, M

]

,

whence the difference

x

0

j

+1

x

0

j

is equal to

LB

and satisfies (16).

I

Lemma 11.

For any

k >

1

and

p

0

>

0

there exists a constant

θ >

0

such that local extrema of any typical solution

y

(

x

)

to equation

(1), ultimately satisfy the inequality

y

(

x

0

j

)

θF

y

(

x

0

j

)

4

.

J

Let

y

(

x

)

be a typical solution to equation (1) and

x

0

j

be its

local extremum point with sufficiently large number. Put

θ

= inf

{|

a

0

|

:

a

E

+

, a

1

= 0

}

>

0

and choose a constant

λ >

0

such that the data

at zero for the solution

z

(

x

) =

λ

4

y

(

λ

k

1

x

+

x

0

j

)

correspond to some

point in

E

+

.

Then

F

z

(0) = 1

and

|

z

(0)

| ≥

θ.

Since

z

(0) =

λ

4

y

(

x

0

j

)

and

F

z

(0) =

λF

y

(

x

0

j

)

,

the lemma is proved.

I

Remark 1.

For typical solutions to

(1)

with their corresponding curves

lying completely in

Ω

+

,

the statements of Lemmas 8, 10, and 11 hold in

the whole domain, not only ultimately.

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

17