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SOME NEW HILBERT-PACHPATTE’S INEQUALITIES

WENGUI YANG

SCHOOL OFMATHEMATICS ANDCOMPUTATIONALSCIENCE

XIANGTANUNIVERSITY, XIANGTAN, 411105 HUNAN, P.R. CHINA

yangwg8088@163.com

Received 05 September, 2008; accepted 2 January, 2009 Communicated by W.S. Cheung

ABSTRACT. Some new Hilbert-Pachpatte discrete inequalities and their integral analogues are established in this paper. Other inequalities are also given in remarks.

Key words and phrases: Hilbert-Pachpatte’s inequality; Hölder’s inequality; Jensen’s inequality; Nonnegative sequences.

2000 Mathematics Subject Classification. 26D15.

1. INTRODUCTION

Letp≥1, q ≥1and{am}and{bn}be two nonnegative sequences of real numbers defined form = 1,2, . . . , k andn = 1,2, . . . , r, wherek andrare natural numbers and defineAm = Pm

s=1asandBn=Pn

t=1bt. Then (1.1)

k

X

m=1 r

X

n=1

ApmBnq

m+n ≤C(p, q, k, r) ( k

X

m=1

(k−m+ 1)(Ap−1m am)2 )12

× ( r

X

n=1

(r−n+ 1)(Bnq−1bn)2 )12

, unless{am}or{bn}is null, whereC(p, q, k, r) = 12pq√

kr.

An integral analogue of (1.1) is given in the following result.

Letp≥1, q ≥1andf(σ)≥ 0, g(τ)≥0forσ ∈(0, x), τ ∈ (0, y),wherex, y are positive real numbers and defineF(s) = Rs

0 f(σ)dσ andG(t) = Rt

0 g(τ)dτ,for s ∈ (0, x), t ∈ (0, y).

Then (1.2)

Z x 0

Z y 0

Fp(s)Gq(t)dsdt

s+t ≤D(p, q, x, y) Z x

0

(x−s)(Fp−1(s)f(s))2ds 12

× Z y

0

(y−t)(Gq−1(t)g(t))2dt 12

,

031-09

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unlessf(σ)≡0org(τ)≡0, whereD(p, q, x, y) = 12pq√ xy.

Inequalities (1.1) and (1.2) are the well known Hilbert-Pachpatte inequalities [1], which gave new estimates on Hilbert type inequalities [2]. It is well known that the Hilbert-Pachpatte inequalities play a dominant role in analysis, so the literature on such inequalities and their applications is vast [3] – [8].

Young-Ho Kim [9] gave new inequalities similar to the Hilbert-Pachpatte inequalities as fol- lows.

Letp ≥1, q ≥1, α >0, and{am}and{bn}be two nonnegative sequences of real numbers defined form = 1,2, . . . , k andn = 1,2, . . . , r, wherekandrare natural numbers and define Am =Pm

s=1asandBn=Pn

t=1bt. Then (1.3)

k

X

m=1 r

X

n=1

ApmBnq

(mα+nα)α1 ≤C(p, q, k, r;α) ( k

X

m=1

(k−m+ 1)(Ap−1m am)2 )12

× ( r

X

n=1

(r−n+ 1)(Bnq−1bn)2 )12

,

unless{am}or{bn}is null, whereC(p, q, k, r;α) = 12α1 pq√

kr.

An integral analogue of (1.3) is given in the following result.

Let p ≥ 1, q ≥ 1, α > 0and f(σ) ≥ 0, g(τ) ≥ 0for σ ∈ (0, x), τ ∈ (0, y), wherex, y are positive real numbers and defineF(s) = Rs

0 f(σ)dσ andG(t) = Rt

0 g(τ)dτ,fors ∈ (0, x), t∈(0, y). Then

(1.4) Z x

0

Z y 0

Fp(s)Gq(t)dsdt

(sα+tα)α1 ≤D(p, q, x, y;α) Z x

0

(x−s)(Fp−1(s)f(s))2ds 12

× Z y

0

(y−t)(Gq−1(t)g(t))2dt 12

, unlessf(σ)≡0org(τ)≡0, whereD(p, q, x, y;α) = 12α1

pq√ xy.

The purpose of the present paper is to derive some new generalized inequalities (1.1) and (1.2) that are similar to (1.3) and (1.4). By applying an elementary inequality, we also obtain some new inequalities similar to some results in [1, 9].

2. MAINRESULTS

Now we give our results as follows in this paper.

Theorem 2.1. Let p ≥ 1, q ≥ 1, α > 1, γ > 1 and {am} and {bn} be two nonnegative sequences of real numbers defined form = 1,2, . . . , k andn = 1,2, . . . , r, wherek andrare natural numbers and defineAm =Pm

s=1asandBn =Pn

t=1bt. Then (2.1)

k

X

m=1 r

X

n=1

ApmBnq

γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤C(p, q, k, r;α, γ)

× ( k

X

m=1

(k−m+ 1)(Ap−1m am)α

)α1 ( r X

n=1

(r−n+ 1)(Bq−1n bn)γ )1γ

,

unless{am}or{bn}is null, whereC(p, q, k, r;α, γ) = α+γpq kα−1α rγ−1γ .

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Proof. The idea for the proof Theorem 2.1 comes from Theorem 1 of [1] and Theorem 2.1 of [9]. From the hypotheses of Theorem 2.1 and using the following inequality (see [10, 11]), (2.2)

( n X

m=1

zm )β

≤β

n

X

m=1

zm ( m

X

k=1

zk )β−1

,

whereβ ≥1is a constant andzm ≥0,(m= 1,2, . . . , n), it is easy to observe that Apm ≤p

m

X

s=1

Ap−1s as, m= 1,2, . . . , k, (2.3)

Bnq ≤q

n

X

t=1

Btq−1bt, n = 1,2, . . . , r.

From (2.3) and Hölder’s inequality, we have (2.4)

m

X

s=1

Ap−1s as ≤mα−1α ( m

X

s=1

(Ap−1s as)α )α1

, m= 1,2, . . . , k,

and (2.5)

n

X

t=1

Btq−1bt≤n

γ−1 γ

( n X

t=1

(Btq−1bt)γ )1γ

, n = 1,2, . . . , r.

Using the inequality of means [12]

(2.6)

( n Y

i=1

sωii )Ωn1

≤ ( 1

n

n

X

i=1

ωisri )1r

forr >0, ωi >0,Pn

i=1ωi = Ωn,we observe that (2.7) (sω11sω22)r/(ω12) ≤ 1

ω121sr12sr2).

Lets1 =mα−1, s2 =nγ−1, ω1 = α1, ω2 = γ1 andr =ω12,from (2.3) – (2.5) and (2.7), we have

ApmBnq ≤pqmα−1α nγ−1γ ( m

X

s=1

(Ap−1s as)α

)1α( n X

t=1

(Btq−1bt)γ )1γ (2.8)

≤ pqαγ α+γ

(m

(α−1)(α+γ) αγ

α + n

(γ−1)(α+γ) αγ

γ )

× ( m

X

s=1

(Ap−1s as)α

)α1 ( n X

t=1

(Btq−1bt)γ )1γ

,

form = 1,2, . . . , k, n= 1,2, . . . , r.From (2.8), we observe that

(2.9) ApmBnq

γm

(α−1)(α+γ)

αγ +αn

(γ−1)(α+γ) αγ

≤ pq α+γ

( m X

s=1

(Ap−1s as)α

)α1 ( n X

t=1

(Btq−1bt)γ )1γ

, form = 1,2, . . . , k, n = 1,2, . . . , r.Taking the sum on both sides of (2.9) first overn from1 torand then overmfrom1tok of the resulting inequality and using Hölder’s inequality with

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indicesα,α/(α−1)andγ,γ/(γ−1)and interchanging the order of summations, we observe that

k

X

m=1 r

X

n=1

ApmBnq γm

(α−1)(α+γ)

αγ +αn

(γ−1)(α+γ) αγ

≤ pq α+γ

k

X

m=1

( m X

s=1

(Ap−1s as)α )1α

r

X

n=1

( n X

t=1

(Bq−1t bt)γ )γ1

≤ pq α+γkα−1α

( k X

m=1 m

X

s=1

(Ap−1s as)α )α1

rγ−1γ ( r

X

n=1 n

X

t=1

(Btq−1bt)γ )γ1

= pq

α+γkα−1α rγ−1γ ( k

X

m=1

(k−m+ 1)(Ap−1m am)α )α1

× ( r

X

n=1

(r−n+ 1)(Bnq−1bn)γ )γ1

.

Remark 1. In Theorem 2.1, setting α = γ = 2, we have (1.1). In Theorem 2.1, setting

1

α +γ1 = 1, we have

k

X

m=1 r

X

n=1

ApmBnq

γmα−1+αnγ−1 ≤C(p, q, k, r;α, γ)

× ( k

X

m=1

(k−m+ 1)(Ap−1m am)α

)α1 ( r X

n=1

(r−n+ 1)(Bq−1n bn)γ )1γ

,

unless{am}or{bn}is null, whereC(p, q, k, r;α, γ) = α+γpq kα−1α rγ−1γ . Remark 2. In Theorem 2.1, settingp=q= 1, we have

(2.10)

k

X

m=1 r

X

n=1

AmBn

γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤C(1,1, k, r;α, γ) ( k

X

m=1

(k−m+ 1)aαm

)α1 ( r X

n=1

(r−n+ 1)bγn )1γ

,

unless{am}or{bn}is null, whereC(1,1, k, r;α, γ) = α+γ1 kα−1α rγ−1γ .

In the following theorem we give a further generalization of the inequality (2.10) obtained in Remark 2. Before we give our result, we point out that{pm}and{qn}should be two positive sequences form= 1,2, . . . , k andn= 1,2, . . . , r in Theorem 2.3 of [9].

Theorem 2.2. Letα >1, γ >1and{am}and{bn}be two nonnegative sequences of real num- bers and{pm}and{qn}be positive sequences defined form = 1,2, . . . , kandn= 1,2, . . . , r, wherek andr are natural numbers and defineAm =Pm

s=1as,Bn =Pn

t=1bt, Pm =Pm s=1ps

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andQn =Pn

t=1qt. LetΦandΨbe two real-valued, nonnegative, convex, and submultiplicative functions defined onR+= [0,∞).Then

(2.11)

k

X

m=1 r

X

n=1

Φ(Am)Ψ(Bn) γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤M(k, r;α, γ) ( k

X

m=1

(k−m+ 1)

pmΦ am

pm

α)α1

× ( r

X

n=1

(r−n+ 1)

qnΨ bn

qn

γ)1γ , where

M(k, r;α, γ) = 1 α+γ

( k X

m=1

Φ(Pm) Pm

α−1α )

α−1 α ( r

X

n=1

Ψ(Qn) Qn

γ−1γ )γ−1γ .

Proof. From the hypotheses ofΦandΨand by using Jensen’s inequality and Hölder’s inequal- ity, it is easy to observe that

Φ(Am) = Φ

PmPm

s=1psas/ps Pm

s=1ps (2.12)

≤Φ(Pm)Φ Pm

s=1psas/ps Pm

s=1ps

≤ Φ(Pm) Pm

m

X

s=1

psΦ as

ps

≤ Φ(Pm) Pm mα−1α

( m X

s=1

psΦ

as ps

α)α1 ,

and similarly,

(2.13) Ψ(Bn)≤ Ψ(Qn)

Qn nγ−1γ ( n

X

t=1

qtΨ

bt qt

γ)1γ .

Lets1 =mα−1, s2 =nγ−1, ω1 = 1α, ω2 = 1γ andr =ω12,from (2.7), (2.12) and (2.13), we have

Φ(Am)Ψ(Bn) (2.14)

≤mα−1α nγ−1γ

Φ(Pm) Pm

( m X

s=1

psΦ

as ps

α)α1

×

Ψ(Qn) Qn

( n X

t=1

qtΨ

bt qt

γ)1γ

≤ αγ α+γ

(m

(α−1)(α+γ) αγ

α +n

(γ−1)(α+γ) αγ

γ

)

Φ(Pm) Pm

( m X

s=1

psΦ

as ps

α)α1

×

Ψ(Qn) Qn

( n X

t=1

qtΨ

bt qt

γ)1γ

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form = 1,2, . . . , k, n= 1,2, . . . , r.From (2.14), we observe that (2.15) Φ(Am)Ψ(Bn)

γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤ 1 α+γ

Φ(Pm) Pm

( m X

s=1

psΦ

as

ps

α)α1

Ψ(Qn) Qn

( n X

t=1

qtΨ

bt

qt

γ)γ1

form= 1,2, . . . , k, n= 1,2, . . . , r.Taking the sum on both sides of (2.15) first overnfrom1 torand then overmfrom1tok of the resulting inequality and using Hölder’s inequality with indicesα,α/(α−1)andγ,γ/(γ−1)and interchanging the order of summations, we observe that

k

X

m=1 r

X

n=1

Φ(Am)Ψ(Bn) γm

(α−1)(α+γ)

αγ +αn

(γ−1)(α+γ) αγ

≤ 1 α+γ

k

X

m=1

Φ(Pm) Pm

( m X

s=1

psΦ

as ps

α)α1

r

X

n=1

Ψ(Qn) Qn

( n X

t=1

qtΨ

bt qt

γ)1γ

≤ 1 α+γ

( k X

m=1

Φ(Pm) Pm

α−1α )α−1α ( k X

m=1 m

X

s=1

psΦ

as ps

α)α1

× ( r

X

n=1

Ψ(Qn) Qn

γ−1γ )γ−1γ ( r X

n=1 n

X

t=1

qtΨ

bt qt

γ)1γ

= 1

α+γ ( k

X

m=1

Φ(Pm) Pm

α−1α )α−1α ( r X

n=1

Ψ(Qn) Qn

γ−1γ )γ−1γ

× ( k

X

m=1

(k−m+ 1)

psΦ as

ps

α)1α( r X

n=1

(r−n+ 1)

qtΨ bt

qt

γ)γ1 .

Remark 3. From the inequality (2.7), we obtain

(2.16) sω11sω22 ≤ 1 ω12

ω1sω1122sω212

for ω1 > 0, ω2 > 0. If we apply the elementary inequality (2.16) on the right-hand sides of (2.1) in Theorem 2.1 and (2.11) in Theorem 2.2, then we get the following inequalities

k

X

m=1 r

X

n=1

ApmBnq

γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤ αγC(p, q, k, r;α, γ) α+γ

 1 α

( k X

m=1

(k−m+ 1)(Ap−1m am)α )

α+γ αγ

+1 γ

( r X

n=1

(r−n+ 1)(Bnq−1bn)γ

)α+γαγ

,

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whereC(p, q, k, r;α, γ) = α+γpq kα−1α rγ−1γ .Also,

k

X

m=1 r

X

n=1

Φ(Am)Ψ(Bn) γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤ αγM(k, r;α, γ) α+γ

 1 α

( k X

m=1

(k−m+ 1)

pmΦ am

pm α)

α+γ αγ

+ 1 γ

( r X

n=1

(r−n+ 1)

qnΨ bn

qn

γ)α+γαγ

,

where

M(k, r;α, γ) = 1 α+γ

( k X

m=1

Φ(Pm) Pm

α−1α )α−1α ( r X

n=1

Ψ(Qn) Qn

γ−1γ )γ−1γ .

The following theorems deal with slight variants of the inequality (2.11) given in Theorem 2.2.

Theorem 2.3. Letα >1, γ >1and{am}and{bn}be two nonnegative sequences of real num- bers defined form = 1,2, . . . , k andn = 1,2, . . . , r, wherek andr are natural numbers and defineAm = m1 Pm

s=1as andBn = 1nPn

t=1bt. Let ΦandΨbe two real-valued, nonnegative, convex functions defined onR+ = [0,∞).Then

k

X

m=1 r

X

n=1

mnΦ(Am)Ψ(Bn) γm

(α−1)(α+γ)

αγ +αn

(γ−1)(α+γ) αγ

≤C(1,1, k, r;α, γ)

× ( k

X

m=1

(k−m+ 1)Φα(am)

)α1 ( r X

n=1

(r−n+ 1)Ψγ(bn) )1γ

,

whereC(1,1, k, r;α, γ) = α+γ1 kα−1α rγ−1γ .

Proof. From the hypotheses and by using Jensen’s inequality and Hölder’s inequality, it is easy to observe that

Φ(Am) = Φ 1 m

m

X

s=1

as

!

≤ 1 m

m

X

s=1

Φ(as)≤ 1 mmα−1α

( m X

s=1

Φα(as) )α−1α

,

Ψ(Bn) = Ψ 1 n

n

X

t=1

bt

!

≤ 1 n

n

X

t=1

Ψ(bt)≤ 1 nn

γ−1 γ

( n X

t=1

Ψγ(bt) )γ−1γ

.

The rest of the proof can be completed by following the same steps as in the proofs of Theo- rems 2.1 and 2.2 with suitable changes and hence we omit the details.

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Theorem 2.4. Let α > 1, γ > 1 and {am} and {bn} be two nonnegative sequences of real numbers and {pm} and {qn} be positive sequences defined for m = 1,2, . . . , k and n = 1,2, . . . , r, wherekandrare natural numbers and definePm =Pm

s=1ps, Qn =Pn t=1qt, Am = P1

m

Pm

s=1pmas andBn = Q1

n

Pn

t=1qnbt. LetΦandΨbe two real-valued, nonnegative, convex functions defined onR+ = [0,∞).Then

k

X

m=1 r

X

n=1

PmQnΦ(Am)Ψ(Bn) γm(α−1)(α+γ)αγ +αn(γ−1)(α+γ)αγ

≤C(1,1, k, r;α, γ) ( k

X

m=1

(k−m+ 1) [pmΦ (am)]α )α1

× ( r

X

n=1

(r−n+ 1) [qnΨ (bn)]γ )1γ

,

whereC(1,1, k, r;α, γ) = α+γ1 kα−1α rγ−1γ .

Proof. From the hypotheses and by using Jensen’s inequality and Hölder’s inequality, it is easy to observe that

Φ(Am) = Φ 1 Pm

m

X

s=1

psas

!

≤ 1 Pm

m

X

s=1

psΦ(as)

≤ 1 Pmmα−1α

( m X

s=1

[psΦ(as)]α )α−1α

,

Ψ(Bn) = Ψ 1 Qn

n

X

t=1

qtbt

!

≤ 1 Qn

n

X

t=1

qtΨ(bt)

≤ 1 Qnnγ−1γ

( n X

t=1

[qtΨ(bt)]γ )γ−1γ

.

The rest of the proof can be completed by following the same steps as in the proofs of Theo- rems 2.1 and 2.2 with suitable changes and hence we omit the details.

3. INTEGRAL ANALOGUES

Now we give the integral analogues of the inequalities in Theorems 2.1 – 2.4.

An integral analogue of Theorem 2.1 is given in the following theorem.

Theorem 3.1. Let p ≥ 0, q ≥ 0, α > 1, γ > 1 and f(σ) ≥ 0, g(τ) ≥ 0 for σ ∈ (0, x), τ ∈ (0, y), wherex,yare positive real numbers, defineF(s) = Rs

0 f(σ)dσ,G(t) = Rt

0 g(τ)dτ

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fors ∈(0, x), t∈(0, y). Then (3.1)

Z x 0

Z y 0

Fp(s)Gq(t) γs(α−1)(α+γ)αγ +αt(γ−1)(α+γ)αγ

dsdt

≤D(p, q, x, y;α, γ) Z x

0

(x−s)(Fp−1(s)f(s))αds 1α

× Z y

0

(y−t)(Gq−1(t)g(t))γdt 1γ

,

unlessf(σ)≡0org(τ)≡0, whereD(p, q, x, y;α, γ) = α+γpq xα−1α yγ−1γ .

Proof. From the hypotheses ofF(s)andG(t), it is easy to observe that Fp(s) = p

Z s 0

Fp−1(σ)f(σ)dσ, s∈(0, x), (3.2)

Gq(t) = q Z t

0

Gq−1(τ)g(τ)dτ, t ∈(0, y).

From (3.2) and Hölder’s inequality, we have (3.3)

Z x 0

Fp−1(σ)f(σ)dσ ≤sα−1α Z s

0

(Fp−1(σ)f(σ))αα1

, s ∈(0, s),

and (3.4)

Z y 0

Gq−1(t)g(t)dt ≤tγ−1γ Z t

0

(Gq−1(τ)g(τ))γ1γ

, t∈(0, t).

Lets1 = sα−1, s2 = tγ−1, ω1 = α1, ω1 = 1γ, r = ω12,from (3.2) – (3.4) and (2.7), we observe that

Fp(s)Gq(t)≤pqsα−1α tγ−1γ Z s

0

(Fp−1(σ)f(σ))α

α1 Z t 0

(Gq−1(τ)g(τ))γγ1 (3.5)

≤ pqαγ α+γ

(m(α−1)(α+γ)αγ

α +n(γ−1)(α+γ)αγ γ

)

× Z s

0

(Fp−1(σ)f(σ))α

α1 Z t 0

(Gq−1(τ)g(τ))γγ1

fors ∈(0, x), t∈(0, y).From (3.5), we observe that (3.6) Fp(s)Gq(t)

γs

(α−1)(α+γ)

αγ +αt

(γ−1)(α+γ) αγ

≤ pq α+γ

Z s 0

(Fp−1(σ)f(σ))α

α1 Z t 0

(Gq−1(τ)g(τ))γγ1

fors ∈ (0, x), t ∈ (0, y).Taking the integral on both sides of (3.6) first over tfrom0toyand then oversfrom0toxof the resulting inequality and using Hölder’s inequality with indicesα,

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α/(α−1)andγ,γ/(γ−1)and interchanging the order of integrals, we observe that Z x

0

Z y 0

Fp(s)Gq(t) γs

(α−1)(α+γ)

αγ +αt

(γ−1)(α+γ) αγ

dsdt

≤ pq α+γ

"

Z x 0

Z s 0

(Fp−1(σ)f(σ))α1α

ds

# "

Z y 0

Z t 0

(Gq−1(τ)g(τ))γ1γ

dt

#

≤ pq α+γxα−1α

Z x 0

Z s 0

(Fp−1(σ)f(σ))αdσds α1

yγ−1γ Z y

0

Z t 0

(Gq−1(τ)g(τ))γdτ dt 1γ

= pq

α+γxα−1α y

γ−1 γ

Z x 0

(x−s)(Fp−1(s)f(s))αds

α1 Z t 0

(y−t)(Gq−1(t)g(t))γdt 1γ

.

Remark 4. In Theorem 3.1, setting α = γ = 2, we have (1.2). In Theorem 3.1, setting

1

α +γ1 = 1, we have Z x

0

Z y 0

Fp(s)Gq(t)

γsα−1+αtγ−1dsdt≤D(p, q, x, y;α, γ)

× Z x

0

(x−s)(Fp−1(s)f(s))αds

1αZ y 0

(y−t)(Gq−1(t)g(t))γdt 1γ

,

unlessf(σ)≡0org(τ)≡0, whereD(p, q, x, y;α, γ) = α+γpq xα−1α yγ−1γ . Remark 5. In Theorem 3.1, settingp=q= 1, we have

(3.7) Z x

0

Z y 0

F(s)G(t) γs

(α−1)(α+γ)

αγ +αt

(γ−1)(α+γ) αγ

dsdt

≤D(1,1, x, y;α, γ) Z x

0

(x−s)fα(s)ds

α1 Z y 0

(y−t)gγ(t)dt 1γ

, unlessf(σ)≡0org(τ)≡0, whereD(1,1, x, y;α, γ) = α+γ1 xα−1α y

γ−1 γ .

In the following theorem we give a further generalization of the inequality (3.7) obtained in Remark 5.

Theorem 3.2. Let α > 1, γ > 1 and f(σ) ≥ 0, g(τ) ≥ 0, p(σ) > 0 and q(τ) > 0 for σ ∈ (0, x), τ ∈ (0, y), wherex, y are positive real numbers. DefineF(s) = Rs

0 f(σ)dσ and G(t) = Rt

0 g(τ)dτ, P(s) = Rs

0 p(σ)dσ and Q(t) = Rt

0 q(τ)dτ for s ∈ (0, x), t ∈ (0, y). Let Φand Ψbe two real-valued, nonnegative, convex, and submultiplicative functions defined on R+ = [0,∞).Then

(3.8) Z x

0

Z y 0

Φ(F(s))Ψ(G(t)) γs

(α−1)(α+γ)

αγ +αt

(γ−1)(α+γ) αγ

dsdt

≤L(x, y;α, γ) Z x

0

(x−s)

p(s)Φ f(s)

p(s) α

ds α1

× Z y

0

(y−t)

q(t)Ψ g(t)

q(t) γ

dt 1γ

,

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where

L(x, y;α, γ) = 1 α+γ

(Z x 0

Φ(P(s)) P(s)

α−1α ds

)α−1α ( Z y

0

Ψ(Q(t)) Q(t)

γ−1γ dt

)γ−1γ . Proof. From the hypotheses ofΦandΨand by using Jensen’s inequality and Hölder’s inequal- ity, it is easy to see that

Φ(F(s))) = Φ

P(s)Rs

0 p(σ)f(σ)

p(σ)

dσ Rs

0 p(σ)dσ

 (3.9) 

≤Φ(P(s))Φ

 Rs

0 p(σ) f(σ)

p(σ)

dσ Rs

0 p(σ)dσ

≤ Φ(P(s)) P(s)

Z s 0

p(σ)Φ

f(σ) p(σ)

≤ Φ(P(s)) P(s) sα−1α

Z s 0

p(σ)Φ

f(σ) p(σ)

α

α1

,

and similarly,

(3.10) Ψ(G(t))≤ Ψ(Q(t))

Q(t) tγ−1γ Z t

0

q(τ)Ψ

g(τ) q(τ)

γ

1γ

.

Lets1 = sα−1, s2 = tγ−1, ω1 = α1, ω1 = 1γ, r = ω12,from (3.9), (3.10) and (2.7), we observe that

Φ(F(s))Ψ(G(t))≤sα−1α tγ−1γ

"

Φ(P(s)) P(s)

Z s 0

p(σ)Φ

f(σ) p(σ)

α

α1# (3.11)

×

"

Ψ(Q(t)) Q(t)

Z t 0

q(τ)Ψ

g(τ) q(τ)

γ

1γ#

≤ αγ α+γ

(m(α−1)(α+γ)αγ

α + n(γ−1)(α+γ)αγ γ

)

×

"

Φ(P(s)) P(s)

Z s 0

p(σ)Φ

f(σ) p(σ)

α

α1#

×

"

Ψ(Q(t)) Q(t)

Z t 0

q(τ)Ψ

g(τ) q(τ)

γ

1γ#

fors ∈(0, x), t∈(0, y).From (3.11), we observe that (3.12) Φ(F(s))Ψ(G(t))

γs(α−1)(α+γ)αγ +αt(γ−1)(α+γ)αγ

≤ 1 α+γ

"

Φ(P(s)) P(s)

Z s 0

p(σ)Φ

f(σ) p(σ)

α

1α#

×

"

Ψ(Q(t)) Q(t)

Z t 0

q(τ)Ψ

g(τ) q(τ)

γ

1γ#

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fors∈(0, x), t∈(0, y).Taking the integral on both sides of (3.12) first overtfrom0toyand then oversfrom0toxof the resulting inequality and using Hölder’s inequality with indicesα, α/(α−1)andγ,γ/(γ−1)and interchanging the order of integrals, we observe that

Z x 0

Z y 0

Φ(F(s))Ψ(G(t)) γs(α−1)(α+γ)αγ +αt(γ−1)(α+γ)αγ

dsdt

≤ 1 α+γ

"

Z x 0

Φ(P(s)) P(s)

Z s 0

p(σ)Φ

f(σ) p(σ)

α

α1

ds

#

×

"

Z y 0

Ψ(Q(t)) Q(t)

Z t 0

q(τ)Ψ

g(τ) q(τ)

γ

γ1

dt

#

≤ 1 α+γ

(Z x 0

Φ(P(s)) P(s)

α−1α ds

)α−1α Z x

0

Z s 0

p(σ)Φ

f(σ) p(σ)

α

dσds α1

× (Z y

0

Ψ(Q(t)) Q(t)

γ−1γ dt

)γ−1γ Z y

0

Z t 0

q(τ)Ψ

g(τ) q(τ)

γ

dτ dt 1γ

= 1

α+γ (Z x

0

Φ(P(s)) P(s)

α−1α ds

)α−1α ( Z y

0

Ψ(Q(t)) Q(t)

γ−1γ dt

)γ−1γ

× Z x

0

(x−s)

p(s)Φ f(s)

p(s) α

ds

α1 Z y 0

(y−t)

q(t)Ψ g(t)

q(t) γ

dt γ1

.

Remark 6. From the inequality (2.7), we obtain

(3.13) sω11sω22 ≤ 1

ω12 ω1sω1122sω212

for ω1 > 0, ω2 > 0. If we apply the elementary inequality (3.13) on the right-hand sides of (3.1) in Theorem 3.1 and (3.8) in Theorem 3.2, then we get the following inequalities

(3.14) Z x

0

Z y 0

Fp(s)Gq(t) γs(α−1)(α+γ)αγ +αt(γ−1)(α+γ)αγ

dsdt

≤ αγD(p, q, x, y;α, γ) α+γ

"

1 α

Z x 0

(x−s)(Fp−1(s)f(s))αds α+γαγ

+ 1 γ

Z y 0

(y−t)(Gq−1(t)g(t))γdt α+γαγ #

,

whereD(p, q, x, y;α, γ) = α+γpq xα−1α yγ−1γ . Also, Z x

0

Z y 0

Φ(F(s))Ψ(G(t)) γs(α−1)(α+γ)αγ +αt(γ−1)(α+γ)αγ

dsdt

≤ αγL(x, y;α, γ) α+γ

"

1 α

Z x 0

(x−s)

p(s)Φ f(s)

p(s) α

ds α+γαγ

(13)

+ 1 γ

Z y 0

(y−t)

q(t)Ψ g(t)

q(t) γ

dt α+γαγ #

,

where

L(x, y;α, γ) = 1 α+γ

x

Z

0

Φ(P(s)) P(s)

α−1α ds

α−1

α (

Z y 0

Ψ(Q(t)) Q(t)

γ−1γ dt

)γ−1γ .

The following theorems deal with slight variants of (3.8) given in Theorem 3.2. Before we state our next theorem, we point out that “F(s) = Rs

0 f(σ)dσ and G(t) = Rt

0g(τ)dτ” are replaced by “F(s) = 1sRs

0 f(σ)dσ andG(t) = 1tRt

0 g(τ)dτ” in Theorem 3.4 in [9].

Theorem 3.3. Let α > 1, γ > 1 and f(σ) ≥ 0, g(τ) ≥ 0 for σ ∈ (0, x), τ ∈ (0, y), where x, y are positive real numbers. Define F(s) = 1sRs

0 f(σ)dσ, G(t) = 1tRt

0 g(τ)dτ for s ∈ (0, x), t ∈ (0, y). LetΦandΨbe two real-valued, nonnegative, convex functions defined onR+ = [0,∞).Then

Z x 0

Z y 0

stΦ(F(s))Ψ(G(t)) γs

(α−1)(α+γ)

αγ +αt

(γ−1)(α+γ) αγ

dsdt

≤D(1,1, x, y;α, γ) Z x

0

(x−s)Φα(f(s))ds

α1 Z y 0

(y−t)Ψγ(g(t))dt 1γ

, whereD(1,1, x, y;α, γ) = α+γ1 xα−1α y

γ−1 γ .

Theorem 3.4. Letα >1, γ >1andf(σ)≥0, g(τ)≥0, p(σ)>0andq(τ)>0forσ∈(0, x), τ ∈(0, y), wherex,yare positive real numbers. DefineP(s) =Rs

0 p(σ)dσ,Q(t) =Rt

0q(τ)dτ, F(s) = P1(s)Rs

0 p(σ)f(σ)dσ andG(t) = Q(t)1 Rt

0 q(τ)g(τ)dτ for s ∈ (0, x), t ∈ (0, y). Let Φ andΨbe two real-valued, nonnegative, convex functions defined onR+ = [0,∞).Then

Z x 0

Z y 0

P(s)Q(t)Φ(F(s))Ψ(G(t)) γs

(α−1)(α+γ)

αγ +αt

(γ−1)(α+γ) αγ

dsdt

≤D(1,1, x, y;α, γ) Z x

0

(x−s) [p(s)Φ (f(s))]αds

1αZ y 0

(y−t) [q(t)Ψ (g(t))]γdt 1γ

, whereD(1,1, k, r;α, γ) = α+γ1 xα−1α y

γ−1 γ .

The proofs of Theorems 3.3 and 3.4 are similar to the proof of Theorem 3.2 and similar to the proofs of Theorems 2.3 and 2.4. Hence, we leave out the details.

REFERENCES

[1] B.G. PACHPATTE, On some new inequalities similar to Hilbert’s inequality, J. Math. Anal. and Appl., 226 (1998), 116–179.

[2] G.H. HARDY, J.E. LITTLEWOODANDG. POLYA, Inequalities, London: Cambridge University Press, 1952.

[3] G.D. HANDLEY, J.J. KOLIHAANDJ. PE ˇCARI ´C, Hilbert-Pachpatte type multidimensional inte- gral inequalities, J. Ineq. Pure and Appl. Math., 5(2) (2004), Art. 34. [ONLINEhttp://jipam.

vu.edu.au/article.php?sid=389].

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[4] C.J. ZHAOANDW.S. CHEUNG, Inverses of new Hilbert-Pachatte type inequalities, J. Inequ. and Appl., 2006 (2006), 1–11.

[5] B.G. PACHPATTE, Inequalities similar to certain extensions of Hilbert’s inequality, J. Math. Anal.

and Appl., 243 (2000), 217–227.

[6] Z.X. LÜ, Some new inequalities similar to Hilbert-Pachpatte type inequalities, J. Ineq. Pure and Appl. Math., 4(2) (2003), Art. 33. [ONLINEhttp://jipam.vu.edu.au/article.php?

sid=271].

[7] J. PE ˇCARI ´C, I. PERI ´CANDP. VUKVI ´C, Hilbert-Pachpatte type inequalities from Bonsall’s form of Hilbert’s inequality, J. Ineq. Pure and Appl. Math., 9(1) (2008), Art. 9. [ONLINE http://

jipam.vu.edu.au/article.php?sid=949].

[8] S.S. DRAGOMIR AND YOUNG-HO KIM, Hilbert-Pachpatte type integral inequalities and their improvement, J. Ineq. Pure and Appl. Math., 4(1) (2003), Art. 16. [ONLINE http://jipam.

vu.edu.au/article.php?sid=252].

[9] YOUNG-HO KIM, An improvement of some inequalities similar to Hilbert’s inequality, Int. J.

Math. and Math. Sci., 28(4) (2001), 211–221.

[10] G.S. DAVISANDG.M. PETERSON, On an inequality of Hardy’s (II), Quart. J. Math. Oxford Ser., 15 (1964), 35–40.

[11] J. NÉMETH, Generalizations of the Hardy-Littlewood inequality, Acta Sci. Math. (Szeged), 32 (1971), 295–299.

[12] D.S. MITRINOVI ´C, J.E. PE ˇCARI ´CANDA.M. FINK, Classical and New Inequalities in Analysis, Kluwer Academic, Dordrecht, 1993.

[13] YOUNG-HO KIMANDBYUNG-IL KIM, An analogue of Hilbert’s inequality and its extensions, Bull. Korean Math. Soc., 39(3) (2002), 377–388.

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