International Journal of Mathematics and Mathematical Sciences Volume 2012, Article ID 809689,12pages
doi:10.1155/2012/809689
Research Article
Hermite-Hadamard and Simpson-Like
Type Inequalities for Differentiable (α, m)-Convex
Mappings
Jaekeun Park
Department of Mathematics, Hanseo University, Chungnam-do, Seosan-si 356-706, Republic of Korea
Correspondence should be addressed to Jaekeun Park,jkpark@hanseo.ac.kr Received 13 July 2011; Revised 13 November 2011; Accepted 28 November 2011 Academic Editor: Jewgeni Dshalalow
Copyrightq2012 Jaekeun Park. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The author establish several Hermite-Hadamard and Simpson-like type inequalities for mappings whose first derivative in absolute value aroused to theqthq≥1power areα, m-convex. Some applications to special means of positive real numbers are also given.
1. Introduction
Recall that, for some fixedα∈0,1andm∈0,1, a mappingf :I⊆0,∞ → Ris said to beα, m-convex on an intervalIif the inequality
ftxm1−ty≤tαfx m1−tαfy 1.1
holds forx, y∈I, andt∈0,1. Denote byKα
mIthe set of all α, m-convex mappings on I. For recent results and generalizations concerningm-convex andα, m-convex mappings, see1–4.
For the simplicities of notations, forf∈Kα
mI, let us denote
a−mbSba
fα, m, r 1 r
fa r−2f
amb
2
fmb
− 1
mb−a
mb
a
fxdx.
In 1, 3, Klariˇci´c Bakula and ¨Ozdemir et al., proved the following Hadamard’s inequalities for mappings whose second derivative in absolute value aroused to the q-th
q≥1power areα, m-convex.
Theorem 1.1. Letf : I ⊆ 0, b∗ → Rbe a twice differentiable mapping on the interiorI0 of an
intervalIsuch thatf ∈L1a, b, wherea, b ∈Iwitha < bandb∗ >0. If|f |qisα, m-convex
ona, bforα, m∈0,12andq≥1 with 1/p1/q1, then the following inequality holds:
a Sba
fα, m,2 ≤ mb−a 2
1 6
1/p
μ f a qmν f b q1/q, 1.3
where
μ 1
α2α3, ν
α25α
6α2α3, 1.4
b Sba
fα, m,6 ≤ mb−a 2
1 2
1/p
μ0 f a qmν0 f b q
1/q
, 1.5
where
μ0
q qα2
Γα2Γq
Γqα1,
ν0 1
q1q2 −
q qα2
Γα2Γq
Γqα1,
1.6
where
Γx
∞
0
e−ttx−1dt, x >0. 1.7
Theorem 1.2. Under the same notations in Theorem 2.2, if |f |q is α, m-convex on a, b for
α, m∈0,12andq >1 with 1/p1/q1, then the following inequality holds:
Sb a
fα, m,2 ≤ mb−a 8
Γp1
Γp3/2 1/p
f a q 1
α1m f
b q α
α1 1/q
. 1.8
Note that forα, m∈ {0,0,α,0,1,0,1, m,1,1,α,1}one obtains the following classes of functions: increasing,α-starshaped, starshaped,m-convex, convex, andα-convex. For the definitions and elementary properties of these classes, see4–8.
For recent years, many authors present some new results about Simpson’s inequality for α, m-convex mappings and have established error estimations for the Simpson’s inequality: for refinements, counterparts, generalizations, and new Simpson’s type inequali-ties, see1–3,6.
Theorem 1.3. Letf : I ⊂ 0,∞ → Rbe an absolutely continuous mapping ona, bsuch that
f ∈Lpa, b, wherea, b∈Iwitha < b. Then the following inequality holds:
Sb a
f1,1,6 ≤ b−a
−1/p
6
2q11
3q1 1/q
f
p. 1.9
The readers can estimate theerror fin the generalized Simpson’s formula without going through its higher derivatives which may not exist, not be bounded, or may be hard to find.
In this paper, the author establishes some generalizations of Hermite-Hadamard and Simpson-like type inequalities based on differentiableα, m-convex mappings by using the following new identity inLemma 2.1and by using these results, obtain some applications to special means of positive real numbers.
2. Generalizations of Simpson-Like Type Inequalities on
K
αm
I
In order to generalize the classical Simpson-like type inequalities and prove them, we need the following lemma6.
Lemma 2.1. Letf :I⊆0, b∗ → Rbe a differentiable mapping on the interiorI0of an intervalI,
wherea, b ∈Iwith 0≤ a < band b∗ > 0. Iff ∈ L1a, b, then, forr ≥ 2 andh ∈0,1with
1/r ≤h≤r−1/r, the following equality holds:
Sba
fα, m, r
1
0
pr, tftam1−tbdt 2.1
forf ∈Kα
ma, band eacht∈0,1, where
pr, t
⎧ ⎪ ⎪ ⎪ ⎨ ⎪ ⎪ ⎪ ⎩
t−1
r t∈
0,1
2
,
t−r−1
r t∈
1 2,1
.
2.2
By the similar way as Theorems1.1–1.3, we obtain the following theorems.
Theorem 2.2. Letf : I⊂ 0, b∗ → Rbe a differentiable mapping onI0such thatf ∈La, b,
wherea, b ∈Iwith 0≤ a < b <∞andb∗ > 0. If|f| ∈Kα
ma, b, for someα, m∈0,12and
mb > a, then, for anyr ≥2, the following inequality holds:
Sb a
fα, m, r ≤μ1
1μ21μ31μ41 fa
ν1
1ν21ν31ν41
where
μ11 1
α1α2rα2,
μ21 1
α1α2rα2
α1r−2α2 2α2α1α2r,
μ31 r−1
α2
α1α2rα2
2α2−3r
2α2α1α2r,
μ41 r−1
α2
α1α2rα2
α2−r
α1α2r,
ν1
1
1 2r2 −μ
1
1,
ν2
1
r−22 8r2 −μ
2
1,
ν3
1
r−22 8r2 −μ
3
1,
ν14 1
2r2 −μ 4
1.
2.4
Proof. FromLemma 2.1and using the properties of the modulus, we have the following:
Sb a
fα, m, r ≤
1/r
0
1
r −t ftam1−tb dt
1/2
1/r
t−1
r ftam1−tb dt
r−1/r
1/2
r−1
r −t ftam1−tb dt
1
r−1/r
t−r−1
r ftam1−tb dt.
2.5
Since|f|isα, m-convex ona, b, we know that for anyt∈0,1
ftam1−tb ≤tα fa m1−tα fb . 2.6
By2.5and2.6, we get the following:
Sb a
fα, m, r ≤
1/r
0
1
r −t
tα fa m1−tα fb dt
1/2
1/r
t− 1 r
r−1/r
1/2
r−1
r −t
tα fa m1−tα fb dt
1
r−1/r
t− r−1 r
tα fa m1−tα fb dt
≤
1/2
0
1r −t tαdt
1
1/2
r−r1 −t tαdt
fa
1/2
0
1r −t 1−tαdt
1
1/2
r−r1−t 1−tαdt
m fb
μ11μ21μ13μ41 fa ν11ν21ν31ν41m fb ,
2.7
which completes the proof.
Corollary 2.3. InTheorem 2.2,iif we chooseα1 andr2, then we have the following:
mb−aSb a
f1, m,2
fa fmb
2 −
1
mb−a
mb
a
fxdx
≤ mb−a
8 fa m fb ,
2.8
andiiif we chooseα1 andr6, then we have the following
mb−aSb a
f1, m,6 1 6
fa 4f
amb
2
fmb
− 1
mb−a
mb
a
fxdx
≤ 5
72mb−a fa m fb .
2.9
Theorem 2.4. Under the same notations inTheorem 2.2, if|f|q ∈ Kα
ma, b, for someα, m ∈
0,12,mb > aandq >1 with 1/p1/q1, then, for anyr≥2, the following inequality holds:
Sb a
fα, m, r
≤
1 2r2
1/p
μ11 fa qν11m fb q1/qμ41 fa qν41m fb q1/q
1 8
r−2
r
21/p
μ21 fa qν12m fb q1/qμ13 fa qν13m fb q1/q
.
Proof. FromLemma 2.1and using the properties of modulus, we have the following:
Sb a
fα, m, r ≤
1/r
0
1
r −t ftam1−tb dt
1/2
1/r
t− 1
r ftam1−tb dt
r−1/r
1/2
r−1
r −t ftam1−tb dt
1
r−1/r
t− r−1
r ftam1−tb dt.
2.11
Using the power-mean integral inequality and α, m-convexity of |f|q for any t ∈
0,1, we have the following
a
1/r
0
1
r −t ftam1−tb
q
dt≤μ11 fa qν11m fb q, 2.12
b
1/2
1/r
t− 1
r ftam1−tb
q
dt≤μ21 fa qν21m fb q, 2.13
c
r−1/r
1/2
r−1
r −t ftam1−tb
q
dt≤μ31 fa qν13m fb q, 2.14
d
1
r−1/r
t−r−1
r ftam1−tb
q
dt≤μ41 fa qν41m fb q. 2.15
By the similar way as the above inequalitiesa–d, we have the following:
a
1/r
0
1
r −t ftam1−tb dt≤
1 2r2
1/p
μ1
1 fa
q
ν1
1m fb
q1/q
b
1/2
1/r
t−1
r ftam1−tb dt≤
1 8
r−2
r
21/p
μ21 fa qν21m fb 1/q,
2.17
c
r−1/r
1/2
r−1
r −t ftam1−tb dt≤
1 8
r−2
r
21/p
μ3
1 fa
q
ν3
1m fb
q1/q
,
2.18
d
1
r−1/r
t−r−1
r ftam1−tb dt≤
1 2r2
1/p
μ41 fa qν14m fb q1/q.
2.19
By2.11and2.16–2.19the assertion2.10holds.
Corollary 2.5. InTheorem 2.4,iif we chooseα1 andr2, then we have that
fa fmb
2 −
1
mb−a
mb
a
fxdx
≤ 6−1/q
8 mb−a fa q
5m fb q1/q5 fa qm fb q1/q,
2.20
andiiif we chooseα1 andr6, then we have that
1
6
fa 4f
amb
2
fmb
− 1
mb−a
mb
a
fxdx
≤mb−a
1
72
1 18
1/q
fa q17m fb q1/q
17 fa qm fb q1/q
25 288
2 5
2/q
×7 fa q11m fb q1/q11 fa q7m fb q1/q.
Theorem 2.6. Under the same notations inTheorem 2.2, if|f|q ∈ Kα
ma, b, for someα, m ∈
0,12,mb > aandq >1 with 1/p1/q1, then, for anyr≥2, the following inequality holds: Sb
a
fα, m, r
≤
1
rp1
1/p
μ12 fa qν21m fb q1/qμ24 fa qν24m fb q1/q
r−2p1 2p1rp1
1/p
μ22 fa
q
ν22m fb
q1/q
μ32 fa qν32m fb q1/q
,
2.22
where
μ12 1
rα1α1,
μ22
rα1−2α1
2α1rα1α1,
μ32 2
α1r−1α1−rα1
2α1rα1α1 ,
μ42 r
α1−r−1α1
rα1α1 ,
ν12 1 r −μ
1
2,
ν22
r−2 2r μ
2
2,
ν32 r−2
2r μ
3
2,
ν42
1
r −μ
4
2.
2.23
Proof. Suppose thatq >1. FromLemma 2.1, using the H ¨older integral inequality, we get the
following:
Sb a
fα, m, r ≤
1/r
0
1
r −t
p
dt
1/p1/r
0
ftbm1−ta q
dt
1/q
1/2
1/r
t−1 r
p
dt
1/p1/2
1/r
ftbm1−ta q
dt
1/q
r−1/r
1/2
r−1
r −t
p
dt
1/pr−1/r
1/2
ftbm1−ta q
dt
1/q
1
r−1/r
t−r−1 r
p
dt
1/p1
r−1/r
ftbm1−ta q
dt
≤
1
rp1
1/p1/r
0
ftbm1−ta qdt
1/q
1 2p1
r−2
r
p11/p1/2
1/r
ftbm1−ta q
dt
1/q
1 2p1
r−2
r
p11/pr−1/r
1/2
ftbm1−ta q
dt
1/q
1
rp1
1/p1
r−1/r
ftbm1−ta q
dt
1/q
,
2.24
where we have used the fact that 1/2<1/p11/p<1. Since|f|q∈Km
αa, bfor some fixedα∈0,1andm∈0,1, we have the followings: 1/r
0
ftb 1−ta q
dt≤μ12 fa
q
ν12m fb
q
,
1/2
1/r
ftb 1−ta qdt≤μ22 fa qν22m fb q,
r−1/r
1/2
ftb 1−ta qdt≤μ3
2 fa
q
ν3
2m fb
q
,
1
r−1/r
ftb 1−ta q
dt≤μ42 fa
q
ν24m fb
q
.
2.25
Hence, if we combine the inequalities in2.24-2.25, we get the desired result.
Corollary 2.7. InTheorem 2.6,iif we chooseα1 andr2, then we have that
fa fmb
2 −
1
mb−a
mb
a
fxdx
≤
1 4
11/q
mb−a fa q3m fb q1/q3 fa qm fb q1/q,
2.26
andiiif we chooseα1 andr6, then we have
1
6
fa 4f
amb
2
fmb
− 1
mb−a
mb
a
fxdx
≤mb−a
1
6 12/q
fa q11m fb q1/q11 fa qm fb q1/q
1 3
21/q
fa q2m fb q1/q2 fa qm fb q1/q,
2.27
3. Applications to Special Means
Now using the results ofSection 2, we give some applications to the following special means of positive real numbersa, b∈Rwithb≥a.
1The arithmetic mean:Aa, b ab/2.
2The geometric mean:Ga, b √ab.
3The logarithmic mean:La, b b−a/lnb−lnafora /b.
4The harmonic mean:Ha, b 2ab/ab.
5The power mean:Mra, b arbr/21/r,r≥1, a, b∈R.
6The generalized logarithmic mean:
Lna, b
bn1−an1
b−an1 1/n
, a /b. 3.1
7The identric mean:
Ia, b
⎧ ⎪ ⎪ ⎨ ⎪ ⎪ ⎩
a ab
1
e
bb
aa
1/b−a
a /b. 3.2
Proposition 3.1. Forn ∈ −∞,0∪1,∞\ {−1}anda, b ∈ 0, b∗withb∗ > 0, we have the
following inequalities:
a|Aan, mnbn−Lnna, mb| ≤
mb−a
8 |n|M n−1
n−1
a, m1/n−1b.
b 1 3Aa
n, mnbn 2 3A
na, mb−Ln na, mb
≤
5 72
mb−a|n|Mnn−1−1a, m1/n−1b.
3.3
Proof. The assertions follow fromCorollary 2.3forfx xn.
Proposition 3.2. Fora, b∈0, b∗, we have the following inequalities:
a H−1a, mb−L−1a, mb ≤
mb−a
8a2b2
M22m1/2a, b,
b 1 3H
−1a, mb 2
3A
−1a, mb−L−1a, mb ≤5mb−a
72a2b2
M22m1/2a, b.
3.4
Proposition 3.3. For n ∈ −∞,0∪1,∞\ {−1} and a, b ∈ 0, b∗, we have the following inequalities:
a|Aan, mnbn−Lnna, mb|
≤
3−1/q
8
mb−a|n| ×
A1/qan−1q,5mbn−1q1/qA1/q5an−1q, mbn−1q1/q
,
b 1 3Aa
n, mnbn 2 3A
na, mb−Ln na, mb
≤
1 72
1 9
1/q
mb−a|n| ×A1/qan−1q,17mbn−1qA1/q17an−1q, mbn−1q
25 288
2 25
1/q
mb−a|n|
×A1/q7an−1q,11mbn−1qA1/q11an−1q,7mbn−1q.
3.5
Proof. The assertions follow fromCorollary 2.5forfx xn.
Proposition 3.4. For n ∈ −∞,0∪1,∞\ {−1} and a, b ∈ 0, b∗, we have the following
inequalities:
a|Aan, mnbn−Lnna, b| ≤
1 221/q
|n|mb−a
×A1/qan−1q,3mbn−1qA1/q3an−1q, mbn−1q,
b 1 3Aa
n, mnbn 2 3A
na, mb−Ln na, mb
≤
1 6
11/q1
3 1/q
|n|mb−a×A1/qan−1q,11mbn−1qA1/q11an−1q, mbn−1q
1 3
21/q
21/q|n|mb−a×A1/qan−1q,2mbn−1qA1/q2an−1q, mbn−1q.
3.6
Proof. The assertions follow fromCorollary 2.7forfx xn.
Proposition 3.5. Fora, b∈0, b∗, we have the following inequalities:
a ln Ia, b
Ga, b
≤ b−a
ab
1 411/q
aq3bq1/q 3aqbq1/q,
b ln Ia, b
G1/3a, bA2/3a, b
≤ b−a
ab
1 6
12/q
aq11bq1/q 11aqbq1/q
1 3
21/q
aq2bq1/q 2aqbq1/q.
3.7
Acknowledgment
The author is so indebted to the referee who read carefully through the paper very well and mentioned many scientifically and expressional mistakes.
References
1 M. Klariˇci´c Bakula, M. E. ¨Ozdemir, and J. Peˇcari´c, “Hadamard type inequalities for m andα, m-convex functions,” Journal of Inequalities in Pure and Applied Mathematics, vol. 9, no. 4, article 96, p. 12, 2008.
2 M. E. ¨Ozdemir, E. Set, and M. Z. Sarikaya, “Some new Hadamard’s type inequalities for co-ordinated m-convex andα, m-convex functions,”rgmia.org/papers/v13e/oss5.pdf.
3 M. E. ¨Ozdemir, M. Avci, and H. Kavurmaci, “Hermite-Hadamard-type inequalities viaα, m-convexity,”
Computers & Mathematics with Applications, vol. 61, no. 9, pp. 2614–2620, 2011.
4 E. Set, M. E. ¨Ozdemir, and M. Z. Sarikaya, “Inequalities of Hermite-Hadamard’s type for functions whose derivatives absolute values are m-convex,” in Proceedings of the AIP Conference, vol. 1309, pp. 861–873, 2010,rgmia.org/papers/v13e/sos6.pdf.
5 M. Alomari and M. Darus, “On some inequalities of Simpson-type via quasi-convex functions and applications,” Transylvanian Journal of Mathematics and Mechanics, vol. 2, no. 1, pp. 15–24, 2010.
6 J. Park, “Generalizations of simpson-like type inequalities for differentiable m-convex and α, m -convex mappings,” Far East Journal of Mathematical Sciences, vol. 55, no. 1, pp. 97–109, 2011.
7 M. Z. Sarikaya, E. Set, and M. E. ¨Ozdemir, “On new inequalities of Simpson’s type for functions whose second derivatives absolute values are convex,” RGMIA Research Report Collection, vol. 13, no. 1, article 1, 2010.
8 G. Toader, “The hierarchy of convexity and some classic inequalities,” Journal of Mathematical
Inequalities, vol. 3, no. 3, pp. 305–313, 2009.
9 S. S. Dragomir, R. P. Agarwal, and P. Cerone, “On Simpson’s inequality and applications,” Journal of
Submit your manuscripts at
http://www.hindawi.com
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Mathematics
Journal ofHindawi Publishing Corporation
http://www.hindawi.com Volume 2014
in Engineering
Hindawi Publishing Corporation http://www.hindawi.com
Differential Equations
International Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Probability and Statistics
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Mathematical PhysicsAdvances in
Complex Analysis
Journal ofHindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Optimization
Journal ofHindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Combinatorics
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014 International Journal of Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Operations Research
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Function Spaces
Abstract and Applied Analysis Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporation http://www.hindawi.com Volume 2014
The Scientific
World Journal
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Decision Sciences
Discrete Mathematics
Journal ofHindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014