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IOSR Journal of Mathematics (IOSR-JM)
e-ISSN: 2278-5728, p-ISSN:2319-765X. Volume 10, Issue 4 Ver. I (Jul-Aug. 2014), PP 61-77 www.iosrjournals.org
www.iosrjournals.org 61 | Page
Certain Subclasses of Analysic P-Valent Functions With Respect
To Other Points
1Hamzat J. O,
2Sangoniyi S. O.
1Department of Pure and Applied Mathematics,Ladoke Akintola University, of Technology, Ogbomoso
P.M.B. 4000, Ogbomoso, Oyo State, Nigeria. 2Department of Mathematics,Emmanuel Alayande College of Education, OyoP.M.B. 1010, Oyo State, Nigeria.
Abstract: Let T be the class of analytic functions of the form:
kk
k zazzf
2
defined in the open unit disk 1: zzD normalized with 0f and 01/ f where is an
arbitrary fixed point in D. The authors study certain
subclasses lpS ns ,,,,,*
, , lpS nc ,,,,,*
, and lpS nsc ,,,,,*
, of analytic p-valent
function with negative coefficients in the unit disk. The results presented in this paper include coefficient bounds
and distortion properties for functions belonging to these subclasses. Further results include linear combination of several functions and radii of starlikeness and convexity for functions belonging to the aforemention
subclasses.
Mathematics Subject Classification: Primary 30C45
Keywords and phrases: Analytic function, Univalent function, Starlikeness, Convexity, Coefficient
inequalities.
I. Introduction
Let T denote the class of functions of the form
kk
k zazzf
2 (1)
which are analytic and univalent in the open unit disk 1: zzD and normalized with 0f
and 01/ f , where is an arbitrary fixed point in D. TS denotes the class of analytic and
univalent functions (see[1, 7, 8]).
Also, let pT be the class of analytic p-valent functions zf of the form
kp
k
kp
pzazzf
1
. (2)
Now, supposing we pose index alpha on (2) such hat
kp
k
kp
pzazzf
1
.
This is,
...2
2
1
1
p
p
p
p
pzazazzf
(3)
Expanding (3) binomially, we have
j
pp
j
j
pzazazzf ...1
2
21
1
where ,1
,..!2
12
.
Finally, we have
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 62 | Page
)(zf kp
k
kp
pzaz
1
(4)
Our motivation for this work is that several authors and researchers (see[1,2,3,4,5,6,7,8,9,10]) to
mention but few have worked extensively on coefficient bounds for functions of the type (2), hardly will you
find coefficient inequalities for the functions of the type (4) perhaps due to the difficulties the index α always
pose. However, in the present paper, the authors aim at generalizing 0.. ei . Here, we let ),( pT be
the class of functions of the form (4) where α is real.
Using Aouf et al derivative operator (see[2,3]), we can write for function
,pTzf that
kp
k
kP
nn
n
p zal
lkpz
l
lpzflI
1
,1
11
1
11,
,0Nn ,Np
,0l
,0
0 and
.1k
At this junction, the authors wish to define the following:
Definition A:
(i.) Let the function zf be defined by (2). Then lpSzf n ,,,* if and only if
,0
,
,
,
/
,
zflI
zflIzn
p
n
p
,0Nn Dz (6)
and lpwSn ,,,* denote the class of starliken functions.
(ii.) Let function zf be defined by (2). Then zf
nsS , lp,,, if and only if
DzNnzflIzflI
zflIzn
p
n
p
n
p
,,0
,,
,0
,,
/
,
. (7)
and lpS ns ,,,*
, denotes the class of starlike functions with respect to symmetric points and is an
arbitrary fixed point in D.
(iii) Let function zf be defined by (2). Then zf ,,,,,,
nsS if and only if
pzflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
p
n
p
n
p
n
p
,,
,
,,
,
,,
/
,
,,
/
,
(8)
for some 0 10,1 and z D where is an arbitrary fixed point in D. We
denote the class of starliken with respect to symmetric points by
nsS , ...,,, lp
Definition B: Let the function zf be defined by (4). Then zf is said to be -n-starlike with
respect to symmetric point if it satisfies the condition:
pzflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
p
n
p
n
p
n
p
,,
,
,,
,
,,
/
,
,,
/
,(9)
where ,0 Nn 10 , 10 ,
11
10
p and z D. We denote the class of
starliken with respect to symmetric points by lpS ns ,,,,,,*
, and is an arbitrary fixed
point in D.
Definition C: Let the function zf be defined by (4). Then zf is said to be starliken with
respect to conjugate point if it satisfies the condition:
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 63 | Page
p
zflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
pw
n
p
n
p
n
pw
,,
,
,,
,
,,
/
,
,,
/
, (10)
where NNn }0{0 , 10 , 10 ,
11
10
p, z D and is arbitrarily fixed in
D. We denote the class of starliken with respect to symmetric points by
ncS . .,,,,,, lp
Definition D: Let the functions zf be defined by (4). Then zf is said to be starliken with
respect to symmetric conjugate points if satisfies the condition:
p
zflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
pw
n
p
n
p
n
pw
,,
,
,,
,
,,
/
,
,,
/
,
(11)
where NNn }0{0 , 10 , 10 , 0
1
1p < 1, z D and is arbitrarily fixed in
D. We denote the class of -n-starlike with respect to symmetric points by
nscS ,. .,,,,,, lp
II. Coefficient Inequalities
Theorem 2.1: Let the function zf be defined by (4) and 0,, ,,
zflIzflI n
p
n
p
for z . Then, zf
nsS ,. l,,,,,, if and only if
kp
n
pp
k
k al
lkppkdr
1
111111)(
1
n
pp
l
lpp
1
11111
(12)
Proof: using (4), (5) and (9), that is
pzflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
p
n
p
n
p
n
p
,,
,
,,
,
,,
/
,
,,
/
,
1k
k
zkapzzf
and
zflI n
p ,,
=
kp
kp
k
n
p
n
zl
lkpz
l
lp
1 1
11
1
11.
For convenience, we let
kp
kp
k
kpppzazzf
1
11
and
zflI n
p ,,
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 64 | Page
kp
kp
n
k
kpp
n
pza
l
lkpz
l
lp
1
111
1
111
1
This implies that
kp
kp
n
k
kpp
n
pza
l
lkpkpz
l
lpp
1
111
1
111
1
n
p
l
lpp
1
)1(1)1(1
kp
kp
n
k
pza
l
lkppk
)(1
1111
1
.
That is
pn
ppz
l
lpp
1
11111
.0
1
11111
1
kp
kp
n
k
kpkpza
l
lkppkpk
Letting ,drz we have
1 1
11111
k
kp
kp
n
kpkpdra
l
lkppkpk
.0
1
11111
n
pp
l
lpp
Therefore, by the maximum modulus theorem, we have .,,,,,,*
, lpSzf ns
For the converse, let us suppose that
.
,,
,
,,
,
,,
/
,
,,
/
,
zflIzfl
zflz
zflIzflI
zflIz
n
p
n
p
n
p
n
p
n
p
n
p
This implies that,
1
1
1111
)1()()1(
k
kp
kp
kppp
p
kp
k
kppp
zapkzp
zapkzp
where
n
l
lp
1
11 and
.
1
11n
l
lkp
Since zz for all z , then we have
1
1
1111
11
k
k
kp
kpp
k
kpk
kp
drapkp
drapkp (13)
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
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If we choose values of z on the real axis so that
zflIzflI
zflIzn
p
n
p
in
pw
,,
,
,,
,is real,
0,, ,,
zflIzflI n
p
n
p , zfor and upon clearing the denominator in (13).
Also letting drz through the real values, then we obtain
kkp
k
kp
k
k
kp
kpdrapkdrapk
1 1
111
pp
pp 111
and this completes the proof of theorem 2.1.
Corollary 2.1: Let the function zf defined by (4) be in the class lpS ns ,,,,,,*
, .
Then, we have
DzandNnkdrpkpk
pa
kkpkp
p
kp
0,1111
111
(14)
where and are as earlier defined.
The equality in (14) is attained for function zf given by
kp
kkpp
ppp
zdrpkpk
pzzf
11)1(
111. (15)
Theorem 2.2: Let the function zf be defined by (4). Then lpSzf nc ,,,,,,*
, if and only
if
1
12121k
k
kp pdrapk (16)
Proof: Using (4), (5) and (10), then
p
zflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
pw
n
p
n
p
n
pw
,,
,
,,
,
,,
/
,
,,
/
,
1k
kp
kp
pzazzf
and
zflI n
p ,,
1 1
11
1
11
k
kp
kp
n
p
n
zal
lkpz
l
lp
Let
1k
kp
kp
pzazzf
and
zflI n
p ,,
=
kp
kp
n
k
p
n
zal
lkpz
l
lp
1 1
1
1
11.
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 66 | Page
From (10), we have
1 1
11
1
11
k
kp
kp
n
p
n
zal
lkppkz
l
lpp
p
n
zl
lpp
1
11)2(
kp
kp
n
k
zal
lkpppk
)(
1
112
1
.
This implies that
p
n
zl
lpp
1
1121
1
.01
1112
k
kp
kp
n
zal
lkppkpk
Hence,
1 1
1112
k
kp
kp
n
zal
lkppkpk
n
l
lpp
1
1112
Letting ,drz we obtain
1 1
1112
k
k
kp
n
dral
lkppkpk
n
l
lpp
1
1112
and the complete the proof of Theorem 2.2.
Corollary 2.2: Let the function zf defined by (4) be in the class .,,,,,,*
, lpS nc
Then, we have
k
kp
n
n
kp
dral
lkpk
l
lpp
a
1
11121
1
1112
(17)
Nnk ,1 and z D.
The equality in (17) is attained for the function zf given by
kp
k
kp
n
n
pz
dral
lppk
l
lpp
zzf
1
1112)1(
1
111)2(
Nnk ,1 and zD. (18)
Theorem 2.3: Let the function zf defined by (4) be in the class .,,,,,,*
, lpS nsc
Then, we have
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 67 | Page
1 1
111111
k
k
kp
n
kpdra
l
lkppk
n
pp
l
lpp
1
11)1()1(1
. (19)
Proof 2.3: Using (4),(5) and (11), we have
p
zflIzflI
zflIzp
zflIzflI
zflIz
n
p
n
p
n
pw
n
p
n
p
n
pw
,,
,
,,
,
,,
/
,
,,
/
,
and
zfpI n
p ,,
kp
kp
nkp
k
p
n
pza
l
lkpz
l
lp
1
111
1
111
1
From (11),we have
p
n
pz
l
lpp
1
111
kp
kp
n
k
kpza
l
lkppk
1 1
111
p
n
pz
l
lpp
1
1111
0
1
11)1(1)(
1
kp
kp
n
k
kp zal
lkppkp
.
This implies that
1 1
1111)1(
k
kp
kp
n
kpza
l
lkppkpk
.0
1
11111
pn
ppz
l
lpp
Letting ,drz then we have
1 1
111111
k
k
kp
n
kpdra
l
lkppk
n
pp
l
lpp
1
11)1()1(1
.
and this ends the proof of theorem 2.3.
Corollary2.3: Let the function zf defined by (4) be in the class lpS nsc ,,,,,,*
, . Then, we have
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 68 | Page
k
kp
n
kp
n
pp
kp
dral
lkppkpk
l
lpp
a
1
11111
1
11111
(20)
k 1 and oNn .
The equality in (20) is attained for the function zf given by
zf
kp
k
kp
n
kp
n
pp
pz
dral
lkppkpk
l
lpp
z
1
11111
1
11111
(21)
k 1 and oNn
III. Distortion Theorem
Theorem 3.1: Let the function zf be defined by (4) be in the class .,,,,,,*
, lpS ns .
Then, we have
in
pp
n
pppi
p
l
lpp
l
lpdrp
l
lpdr
1
11111
1
1111̀1
1
11
11
zflI i
p ,,
in
pp
n
pppi
p
l
lpp
l
lpdrp
l
lpdr
1
11111
1
1111̀1
1
11
11
(22)
for Dz , where ni 0 and is arbitrarily fixed in D. The result is best possible.
Proof 2.3: We note that .,,,,,,*
, lpSzf ns if and only if
lpSzflI ins
i
p ,,,,,,, *
,,
and
kp
kp
k
i
p
i
i
p zal
lpz
l
lpzflI
1
,1
1
1
11, . (23)
Now, using theorem 2.1 we have
1 1
11
k
kp
i
al
lkp
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
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drl
lpp
l
lp
l
lpp
n
pp
in
pp
1
11111
1
1
1
11111
11
. (24)
That is,
kp
k
i
al
lk
1 1
11
drl
lpp
l
lpp
in
pp
n
pp
1
11111
1
11111
11
. (25)
It follow from (23) and (25) that
zflI i
p ,,
kp
k
kp
ip
i
zal
lkpz
l
lp
1 1
11
1
11
1
1
1
11
1
11
k
kp
i
p
i
pa
l
lkpdr
l
lpdr
in
pp
n
pppi
p
l
lpp
l
lpdrp
l
lpdr
1
11111
1
11111
1
11
11
(26)
nd also
zflI i
p ,,
in
pp
n
ppp
i
p
l
lpp
l
lpdrp
l
lpdr
1
11111
1
11111
1
11
11
(27)
Finally, we see that the inequality in (22) is attained by the function
zflI i
p ,,
p
i
zl
lp
1
11
kp
in
pp
n
pp
z
drl
lpp
l
lpp
1
11111
1
11111
11
(28)
or by
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 70 | Page
kp
n
pp
n
pp
pz
drl
lpp
l
lpp
zzf
1
11111
1
11111
11
(29)
and this complete the proof of theorem 3.1.
Corollary 3.1: Let the function zf be defined by (4) be in the class .,,,,,,*
, lS ns . Then, we
have
zf
l
lpp
l
lpp
drn
pp
n
pp
p
1
11111
1
11111
11
n
pp
n
pp
p
l
lpp
l
lpp
dr
1
11111
1
11111
11
(30)
for Dz , where is arbitrarily fixed in D .The result is best possible for the function zf given by (29).
Proof: For 0i in theorem 3.1, we can easily show (30).
Theorem3.2: Let the function zf defined by (4) be in the class lpS inc ,,,,,,*
, .
Then, we have
in
np
l
lp
l
lpdrp
p
l
lpdr
1
1121
1
1112
1
11
zflI i
p ,,
in
n
pi
p
l
lpp
l
lpdrp
l
lpdr
1
1121
1
1112
1
11
(31)
for Dz , where ni 0 and is arbitrarily fixed in D. The result is best possible for the function
zf given by
zflI i
p ,,
kp
in
n
p
i
z
drl
lpp
l
lpp
zl
lp
1
1121
1
1112
1
11 (32)
or by
kp
n
n
pz
drl
lpp
l
lpp
zzf
1
1121
1
1112
. (33)
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
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Corollary 3.2: Let the function )(zf defined by (4) be in the class .,,,,,,*
, lpS nc
Then, we have
)(
1
11)2(1
1
)1(11)2(
zf
l
lpp
l
lpdrp
drn
n
p
p
n
n
p
p
l
lpp
l
lpdrp
dr
1
11)2(1
1
)1(11)2(
(34)
for Dz , where is arbitrarily fixed in D .The result is best possible for the function )(zf given by (33).
Theorem 3.3: Let the function )(zf defined by (4) be in the class
lpS insc ,,,,,,*
, .
Then, we have
in
pp
n
pppi
p
l
lpp
l
lpdrp
l
lpdr
1
1)1()1(11
1
)1(1)1()1(1)(
1
)1(1
11
)(),(, zflI i
p
in
pp
n
pppi
p
l
lpp
l
lpdrp
l
lpdr
1
1)1()1(11
1
)1(1)1()1(1)(
1
)1(1
11
(35)
for Dz , where ni 0 and is arbitrarily fixed in D. This result is sharp. Our next results shall include
linear combinations of several functions of the type (4).
IV. 4. Convex linear Combination
Theorem 4.1: Let
Npandzzf p
p ,0,)()( (36)
and
)(zf kp
.)(
)(1
)1(1)1()1(1)1(
1
)1(1)1()1(1
kp
k
n
kpkp
n
pp
pz
drl
lkppk
l
lpp
z
(37)
Then, lpSzf ns ,,,,,,)( *
, if and only if it can be expressed in the form:
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 72 | Page
0
)()(k
kpkp zfzf
, (38)
where
100
k
kpkp and . (39)
Proof: Let
0
)()(k
kpkp zfzf
1
)()(k
kpkppp zfzf
. (40)
Using (36), (37), (38) and (39), it is easily seen that
)(zf
.)(
)(1
)1(1)1()1(1)1(
1
)1(1)1()1(1
kp
k
n
kpkp
kp
n
pp
pz
drl
lkppk
l
lpp
z
(41)
since
kp
kn
pp
k
n
kpkp
l
lpp
drl
lkppk
1
1
)1(1)1()1(1
)(1
)1(1)1()1(1)1(
1
.
)(1
)1(1)1()1(1)1(
1
)1(1)1()1(1
k
kp
k
n
kpkp
n
pp
drl
lkppk
l
lpp
11 p . (42)
It follows from theorem 2.1 that the function lpSzf ns ,,,,,,)( *
, . Conversely,
let us suppose that lpSzf ns ,,,,,,)( *
, . Since
k
n
kpkp
n
pp
kp
drl
lkppk
l
lpp
a
)(1
)1(1)1()1(1)1(
1
)1(1)1()1(1
DzandNnNpk 10,10,1,,,1 0 .
Setting
n
pp
k
n
kpkp
kp
l
lpp
drl
lkppk
1
)1(1)1()1(1
)(1
)1(1)1()1(1)1(
and
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 73 | Page
1
1k
kpp .
It follows that
0
)()(k
kpkp zfzf
and this completes the proof of the theorem.
Corollary 4.1: The extreme points of the class lpS ns ,,,,,,*
, are functions given by (36) and (37).
Theorem 4.2: Let
Npandzzf p
p ,0,)()( (43)
and
)(zf kp
kp
n
pp
n
p z
drl
lpp
l
lpp
z
)(1
1)1()1(11
1
)1(112
)(11
(44)
Then, lpSzf nc ,,,,,,)( *
, if and only if it can be expressed in the form
0
)()(k
kpkp zfzf
, (45)
where
100
k
kpkp and . (46)
The proof is similar to that of theorem 4.1.
Corollary 4.2: The extreme points of the class lpS nc ,,,,,,*
, are functions given by (43) and (44).
Theorem 4.3. Let
Npandzzf p
p ,0,)()( (47) and
)(zf kp pz )(
.
)(1
)1(1)1()1(1)1(
1
)1(1)1()1(1
kp
k
n
kpkp
n
pp
z
drl
lkppk
l
lpp
48)
Then, lpSzf nsc ,,,,,,)( *
, if and only if it can be expressed in the form:
0
)()(k
kpkp zfzf
, (49)
where
100
k
kpkp and .
The proof is also similar to that of theorem 4.1.
Corollary 4.3: The extreme points of the class lpS nsc ,,,,,,*
, are functions given by (47) and (48).
Theorem 4.4: The class lpS ns ,,,,,,*
, is closed under convex linear combination.
Proof: Let us suppose that the function )(1 zf and
)(2 zf defined by
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
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);2,1()()()(1
,
zjazzfk
jkp
p
j (50)
are in the class lpS ns ,,,,,,*
, .
Setting
)10(,)()1()()( 21 zfzfzf . (51)
Then from (50), we can write
);10()()()1()()()(1
2,1, Dzzaazzf kp
k
kpkp
p
(52)
Thus, in view of theorem 2.1, we can have that
)()1()()()1()1(1)1( 2,1,
1
kpkp
k
k
kpkp aadrpk
)()()1()1(1)1( 1,
1
kp
k
k
kpkp adrpk
)()()1()1(1)1()1( 2,
1
kp
k
k
kpkp adrpk
pppp pp )1()1(1)1()1()1(1
ppp )1()1(1 ,
nn
l
lpand
l
lkp
1
)1(1
1
)1(1
which show that lpSzf ns ,,,,,,)( *
, and this complete the proof of theorem 4.4.
Theorem 4.5: the class lpS nc ,,,,,,*
, is closed under convex linear combination.
Proof: Let us suppose that the function )(1 zf and
)(2 zf defined by
);2,1()()()(1
,
zjazzfk
jkp
p
j (53)
are in the class lpS nc ,,,,,,*
, .
Setting
)10(,)()1()()( 21 zfzfzf . (54)
Then from (53), we can write
).;10()()()1()()()(1
2,1, Dzzaazzf kp
k
kpkp
p
(55)
Then from (54), we can write
5. Radii of starlikeness and convexity
Theorem 5.1: Let the function)(zf defined by (4) in the class lpS ns ,,,,,,*
, .
Then )(zf is starlike of order )10( in 1|| rz , where
.
1
)1(1)1()1(1)1(
)(1
)1(1)1()1(1)1()(
inf
1
1
k
n
pp
k
n
kpkp
k
l
lppkp
drl
lkppkp
r
(56)
The result is best possible with the extremal function given by (15) and 1r attains its infimum for 1k .
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 75 | Page
Proof: It is ample to show that
)(
))()((
zf
zfz
for 1rz . This implies that
p
zaz
zak
kp
k kp
p
kp
kpk
1
11
or
pza
zak
k
k kp
k
kpk
1
1
1
1.
That is
1
11
p
zapkk
kpk. (57)
From theorem 2.1, we have
.1
1
111111
1
1111111
1
n
pp
kp
n
k
kpkpk
l
kpp
al
kppkdr
(58)
Hence, (57) is proven true if
p
zpkk
1
n
pp
n
kpk
l
kpp
l
kppkdr
1
111111
1
1111111
.
That is,
k
n
pp
k
n
kpkp
l
lppkp
drl
lkppkp
z
1
1
)1(1)1()1(1)1(
)(1
)1(1)1()1(1)1()(
1k
and this ends the proof of theorem 5.1.
Remark: It is clear that 1r attains its infimum at 1k for the function zf given by
kp
n
pp
n
pp
pz
l
lpp
l
lpp
zzf
1
11111
1
11111
11
.
Theorem 5.2: Let the function zf defined by (4) be in the class lpS nc ,,,,,,*
, . Then zf is
starlike of order 10 in 2rz , where
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 76 | Page
k
n
k
n
k
l
kpp
drl
kppkp
r
1
1
11112
1
111121
inf2
. (59)
The result is best possible with the extremal function given by (18) and 2r attains its infimum for 1k . The
proof is similar to that of Theorem 5.1.
Theorem 5.3: Let the function zf defined by (4) be in the class lpS nsc ,,,,,,*
, . Then zf is
starlike order 10 in 3rz , where
k
n
pp
k
n
kpkp
k
l
ppkpk
drl
kppkp
r
1
1
111111
1
1111111
inf3
(60)
Proof: It is ample to show that
ppf
fzi
//
1
for 1rz . This implies that
p
zakpzp
zakpk
kp
kpk
p
kp
kpk
1
1
1
1
1
or
p
zap
kp
zap
kpk
k
kpk
k
kpk
1
1
1
.
That is,
11
pp
zapkpkk
kpk. (61)
Now, (61) is proven true if
pp
zapkpkk
kp
n
pp
n
kpkpk
l
pp
l
kppkdr
1
111111
1
1111111
. (62)
Solving for z , we have that
Certain Subclasses of Analysic P-Valent Functions With Respect To Other Points
www.iosrjournals.org 77 | Page
.
1
111111
1
1111111
1
k
n
pp
k
n
kpkp
l
ppkpk
drl
kppkp
z
This completes the proof of theorem 5.3.
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