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Fixed Point theorems for multiplicative

Contraction mappings on Multiplicative

Cone - b metric spaces

A.Mary Priya Dharsini 1 and Dr.U.Karuppiah 2

1. Department of Mathematics,

Holy Cross College (Autonomous), Trichy-620 002.

2. Department of Mathematics, St. Joseph's College (Autonomous), Trichy-620 002.

Abstract: The purpose of this work is to use some contraction mappings in the sense of multiplicative Cone - b metric space and prove some fixed point theorems in setting of complete multiplicative cone - b metric space.

Keywords: Multiplicative Cone b - metric space, Fixed point, Multiplicative kannan contraction, Multiplicative Chatterjea - contraction.

Mathematics Subject classification: Primary 47h10, Secondary 54h25.

1. Introduction

Metric Fixed point theory is an essential part of Mathematical Analysis because of its applications in different areas like variational and linear inequalities, improvement and approximation theory. The fixed point theorem in metric spaces plays a significant role to construct methods to solve the problem in Mathematics and Sciences. Although metric fixed point theory is vast field of study and is capable of solving many equations.

In this paper, we proved some fixed point theorems using some contractive conditions in Multiplicative Cone - b metric spaces. The study of fixed point of mappings satisfying certain contraction conditions has many applications and has been at the centre of various research activities.

2. Preliminaries

We recall some definitions Properties for b-metric spaces given by Czerwik [ 14 ] ,multiplicative cone โ€“b metric spaces [16 ] and Consistent with Haung and Zhang[9] and Hussain and shah[10] , will be needed the following definitions in this paper.

Suppose E be a real Banach space and P be a subset of E. Then P is called Cone iff:

(i) P is closed, nonempty and P โ‰  0 .

(ii) ๐‘๐‘ฅ + ๐‘‘๐‘ฆ โˆˆ ๐‘ƒ for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘ƒ and non - negative real numbers c, d.

(iii) ๐‘ƒ โˆฉ โˆ’๐‘ƒ = 0 .

Definition 2.1[9] Suppose P be a Cone in real Banach space E, define a partial ordering โ‰ค with respect to P by ๐‘Ž โ‰ค ๐‘ โŸบ ๐‘ โˆ’ ๐‘Ž โˆˆ ๐‘ƒ. We can write

๐‘Ž < ๐‘ to show that ๐‘Ž โ‰ค ๐‘ and ๐‘Ž โ‰  ๐‘ while ๐‘Ž โ‰ช ๐‘ will stand for ๐‘ โˆ’ ๐‘Ž โˆˆ ๐‘–๐‘›๐‘ก ๐‘ƒ, where int P denotes interior of P.

Definition 2.2[3] Let X be a non-empty set. Let the mapping ๐‘‘: ๐‘‹ ร— ๐‘‹ โŸถ ๐‘… satisfies:

(i) 1โ‰ค ๐‘‘ ๐‘ฅ, ๐‘ฆ for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘Œ with ๐‘ฅ โ‰  ๐‘ฆ; (ii) ๐‘‘ ๐‘ฅ, ๐‘ฆ = 1 if and only if x = y; (iii) ๐‘‘ ๐‘ฅ, ๐‘ฆ = ๐‘‘ ๐‘ฆ, ๐‘ฅ for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘ฅ;

(iv) ๐‘‘ ๐‘ฅ, ๐‘ฆ โ‰ค ๐‘‘ ๐‘ฅ, ๐‘ง . ๐‘‘(๐‘ง, ๐‘ฆ) for all ๐‘ฅ, ๐‘ฆ, ๐‘ง โˆˆ ๐‘‹. Then the function d is said to be a multiplicative metric on X and (X,d) is called a cone multiplicative metric space.

Definition 2.3[10] Suppose that ๐‘‹ be a non-empty set and ๐‘  โ‰ฅ 1 be a given positive real number. A function ๐‘‘: ๐‘‹ ร— ๐‘‹ โŸถ ๐‘… is said to be cone b- metric if and only if โˆ€ ๐‘ฅ, ๐‘ฆ, ๐‘ง โˆˆ ๐‘‹ , the following conditions are satisfied:

(i) 0โ‰ค ๐‘‘ ๐‘ฅ, ๐‘ฆ for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘Œ with ๐‘ฅ โ‰  ๐‘ฆ; (ii) ๐‘‘ ๐‘ฅ, ๐‘ฆ = 0 if and only if x = y; (iii) ๐‘‘ ๐‘ฅ, ๐‘ฆ = ๐‘‘ ๐‘ฆ, ๐‘ฅ for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹;

(iv) ๐‘‘ ๐‘ฅ, ๐‘ฆ โ‰ค ๐‘ [๐‘‘ ๐‘ฅ, ๐‘ง + ๐‘‘ ๐‘ง, ๐‘ฆ ] for all ๐‘ฅ, ๐‘ฆ, ๐‘ง โˆˆ

๐‘‹.

Then the function d is said to be a cone b- metric on X and (X,d) is called a cone b- metric space.

Definition 2.4 [16]: Let ๐‘‹ be a non-empty set and

๐‘  โ‰ฅ 1 be a given positive real number. A mapping

๐‘‘: ๐‘‹ ร— ๐‘‹ โŸถ ๐‘… satisfies:

(2)

(iv) ๐‘‘ ๐‘ฅ, ๐‘ฆ โ‰ค [๐‘‘ ๐‘ฅ, ๐‘ง . ๐‘‘ ๐‘ง, ๐‘ฆ ]๐‘  for all ๐‘ฅ, ๐‘ฆ, ๐‘ง โˆˆ

๐‘‹.

Then the function d is said to be a multiplicative cone b- metric on X and (X,d) is called a multiplicative cone b- metric space.

Example 2.5[14]: Let ๐‘‘ ๐‘ฅ, ๐‘ฆ = ๐‘Ž( โˆž๐‘–=1 ๐‘ฅ๐‘–โˆ’๐‘ฆ๐‘–๐‘) 1 ๐‘

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹; ๐‘ƒ > 1.

We show that ๐‘‘ ๐‘ฅ, ๐‘ฆ is multiplicative cone b - metric space i.e., (๐‘š๐‘๐‘, ๐‘‘), but not multiplicative cone metric space i.e., (๐‘š๐‘, ๐‘‘)

Definition 2.6[12](Multiplicative Convergence)

Let (X, d) be a multiplicative metric space, (๐‘ฅ๐‘›) be a sequence in X and ๐‘ฅ โˆˆ ๐‘‹. If for every multiplicative open ball ๐ต๐‘’ ๐‘ฅ , there exists a natural number N such that ๐‘› โ‰ฅ ๐‘ โ‡’ ๐‘ฅ๐‘›โˆˆ ๐ต๐‘’ ๐‘ฅ , then the sequence (๐‘ฅ๐‘›) is said to be multiplicative convergent to x, denoted by ๐‘ฅ๐‘› โŸถโˆ—๐‘ฅ (nโŸถโˆž). Lemma 2.7:[12] Let (X, d) be a multiplicative metric space, (๐‘ฅ๐‘›) be a sequence in X. If the sequence (๐‘ฅ๐‘›) is multiplicative convergent, then the multiplicative limit point is unique.

Theorem 2.8:[6,7 ] Let (X,d) be a Complete metric spaces and ๐‘‡: ๐‘‹ โŸถ ๐‘‹ be a Kannan Contraction mapping (ie)

d(Tx, Ty) โ‰ค ๐พ[๐‘‘ ๐‘ฅ, ๐‘‡๐‘ฅ + ๐‘‘ ๐‘ฅ, ๐‘‡๐‘ฆ ] for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where Kโˆˆ [0,12). Then T has a unique fixed point.

Theorem 2.9 : [6,7] Let (X,d) be a Complete metric spaces and ๐‘‡: ๐‘‹ โŸถ ๐‘‹ be a Chatterjea- Contraction mapping (ie)

d(Tx, Ty) โ‰ค ๐พ[๐‘‘ ๐‘ฅ, ๐‘‡๐‘ฆ + ๐‘‘ ๐‘ฆ, ๐‘‡๐‘ฅ ] for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where Kโˆˆ [0,12). Then T has a unique fixed point.

Definition 2.10 :[12] Let (X, d) be a multiplicative metric space. A self mapping f is said to be multiplicative Kannan contraction if

๐‘‘ ๐‘“๐‘ฅ, ๐‘“๐‘ฆ โ‰ค ๐‘‘ ๐‘“๐‘ฅ, ๐‘ฅ . ๐‘‘ ๐‘“๐‘ฆ, ๐‘ฆ ๐œ†,

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where ๐œ† โˆˆ [0,12).

Definition 2.11 [12] Let (X, d) be a multiplicative metric space. A self mapping f is said to be multiplicative Chatterjea contraction if

๐‘‘ ๐‘“๐‘ฅ, ๐‘“๐‘ฆ โ‰ค ๐‘‘ ๐‘“๐‘ฅ, ๐‘ฆ . ๐‘‘ ๐‘“๐‘ฆ, ๐‘ฅ ๐œ†,

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where ๐œ† โˆˆ [0,12).

Lemma 2.12 :[16]Suppose that {gm} be a sequence

in real Banach Space E and P be a cone. If c โˆˆ ๐‘–๐‘›๐‘ก ๐‘ƒ and gmโ†’ 1 as (m โ†’โˆž), then there exist

N such that for all m >N , we have gmโ‰ช ๐‘.

Lemma 2.13:[16] Suppose P ba a Cone and gโ‰ช ๐‘ for all c โˆˆ ๐‘–๐‘›๐‘ก ๐‘ƒ ,then g=1.

Lemma 2.14:[16] Suppose P ba a Cone .If gโˆˆ ๐‘ƒ and g โ‰ค ๐‘”๐‘˜ for some ๐‘˜ โˆˆ [0,1), then g=1.

Theorem 2.15:[16] Let (X, d) be a complete multiplicative cone b-metric space with power

๐‘  โ‰ฅ 1. Suppose the mapping ๐‘‡: ๐‘‹ โ†’ ๐‘ฅ satisfies the following contractive condition,

๐‘‘(๐‘‡๐‘Ž, ๐‘‡๐‘) โ‰ค๐‘‘(๐‘Ž, ๐‘)๐œ† for all ๐‘Ž, ๐‘ โˆˆ ๐‘‹ where 0 โ‰ค ๐œ† < 1 is a constant. Then T has a unique fixed point in X.

Theorem 2.16:[15] Let X be a Complete metric space with metric ๐‘‘ and let ๐‘‡: ๐‘‹ โ†’ ๐‘‹ be a function with the property

๐‘‘ ๐‘‡ ๐‘ฅ , ๐‘‡ ๐‘ฆ โ‰ค ๐‘Ž๐‘‘ ๐‘ฅ, ๐‘‡ ๐‘ฅ + ๐‘๐‘‘ ๐‘ฆ, ๐‘‡ ๐‘ฆ + ๐‘๐‘‘ ๐‘ฅ, ๐‘ฆ

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹ where a, b, c are non-negative and satisfy a+b+c < 1. Then T has a unique fixed point.

Theorem 2.17:[15] Let X be a Complete b - metric space with metric ๐‘‘ and let ๐‘‡: ๐‘‹ โ†’ ๐‘‹ be a function with the following condition

๐‘‘ ๐‘‡ ๐‘ฅ , ๐‘‡ ๐‘ฆ โ‰ค ๐‘Ž๐‘‘ ๐‘ฅ, ๐‘‡ ๐‘ฅ + ๐‘๐‘‘ ๐‘ฆ, ๐‘‡ ๐‘ฆ + ๐‘๐‘‘ ๐‘ฅ, ๐‘ฆ

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹ where a, b, c are non-negative and satisfy a+s(b+c) < 1 for ๐‘  โ‰ฅ 1. Then T has a unique fixed point.

3. Main Results

In this section, we prove some fixed theorems using Multiplicative Kannan contraction and multiplicative Chatterjea - contraction and one more contractive conditions in multiplicative cone b - metric spaces. Our main result is follow as:

Theorem 3.1 Let (X, d) be a complete multiplicative cone b- metric space with power

๐‘  โ‰ฅ 1. Suppose the mapping ๐‘‡: ๐‘‹ โ†’ ๐‘‹ satisfies the following Kannan contractive condition,

๐‘‘ ๐‘‡๐‘ฅ, ๐‘‡๐‘ฆ โ‰ค ๐‘‘ ๐‘‡๐‘ฅ, ๐‘ฅ . ๐‘‘ ๐‘‡๐‘ฆ, ๐‘ฆ ๐œ†,

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where 0 โ‰ค ๐œ† <12 is a constant. Then T has a unique fixed point in X and for any

๐‘ฅ โˆˆ ๐‘‹, iterative sequence (๐‘‡๐‘›๐‘ฅ) converges to the fixed point.

Proof. Choose ๐‘ฅ0โˆˆ ๐‘‹. We construct the iterative sequence {๐‘ฅ๐‘›}, where ๐‘ฅ1= ๐‘‡๐‘ฅ0 , ๐‘ฅ2= ๐‘‡๐‘ฅ1=

๐‘‡2๐‘ฅ

0,..., ๐‘ฅ๐‘›= ๐‘‡๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›+1 = ๐‘‡๐‘ฅ๐‘› = ๐‘‡๐‘›+1๐‘ฅ0, ๐‘› โ‰ฅ

1, we have

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โ‰ค (๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘ฅ๐‘› . ๐‘‘ ๐‘‡๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›โˆ’1) ๐œ†

โ‰ค โ‹ฏ โ‰ค (๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1 ) ๐œ† 1โˆ’๐œ† โ‰ค ๐‘‘(๐‘ฅ1, ๐‘ฅ0)๐‘•

for all nโˆˆ โ„•, where h = 1โˆ’๐œ†๐œ† < 1 .For n > m.

๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘š

โ‰ค (๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1 . ๐‘‘ ๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›โˆ’2 โ€ฆ ๐‘‘ ๐‘ฅ๐‘š+1, ๐‘ฅ๐‘š )๐‘  โ‰ค

(๐‘‘(๐‘ฅ1, ๐‘ฅ0)๐‘•

๐‘› โˆ’1+๐‘•๐‘› โˆ’2+โ‹ฏ+๐‘•๐‘š

)๐‘  โ‰ค (๐‘‘(๐‘ฅ1, ๐‘ฅ0)

๐‘• ๐‘š

1โˆ’๐‘•)๐‘ 

โ‰ค ๐‘‘(๐‘ฅ1, ๐‘ฅ0) ๐‘ ๐‘•๐‘š 1โˆ’๐‘ ๐‘•

This implies ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘š โ†’ 1 ๐‘›, ๐‘š โ†’โˆž . (i.e) ๐‘‘(๐‘ฅ1, ๐‘ฅ0)

๐‘ ๐‘• ๐‘š

1โˆ’๐‘ ๐‘•โ†’ 1 as mโ†’โˆž for any ๐‘  โ‰ฅ 1.

Hence {๐‘ฅ๐‘›} is a Cauchy sequence. Since (X,d) is a Complete multiplicative Cone b-metric space, there exist ๐‘ง ๐‘–๐‘› ๐‘‹ such that ๐‘ฅ๐‘› โ†’ ๐‘ง ๐‘› โ†’โˆž . for all n > n0 .

d(Tz,z) โ‰ค (๐‘‘ ๐‘‡๐‘ง, ๐‘‡๐‘ฅ๐‘› . ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘ง )๐‘ 

โ‰ค ๐‘‘ ๐‘‡๐‘ง, ๐‘‡๐‘ฅ๐‘› ๐‘ . ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘ง ๐‘ 

โ‰ค (๐‘‘ ๐‘‡๐‘ง, ๐‘ง . ๐‘‘ ๐‘ง, ๐‘‡๐‘ฅ๐‘› )๐‘ ๐œ†. ๐‘‘(๐‘ฅ๐‘›+1,๐‘ง)๐‘ 

โ‰ค (๐‘‘ ๐‘‡๐‘ง, ๐‘ง ๐‘ ๐œ† . ๐‘‘(๐‘ฅ

๐‘›+1,๐‘ง)๐‘ ๐œ† +๐‘  โ‰ค๐‘‘ ๐‘ฅ๐‘›+1,๐‘ง

๐‘ (๐œ† +1)

1โˆ’๐‘ ๐œ† โ‰ช ๐‘ , for each n > n

0.

we have

By use of lemma 2.12 ,we deduce that ๐‘‘ ๐‘‡๐‘ง, ๐‘ง =

1. This implies Tz = z. So z is a fixed point of T. For proving uniqueness, if there is another fixed point z1, then by the given assertion,

d(z, z1) = d(Tz,Tz1)

โ‰ค (๐‘‘(๐‘‡๐‘ง , ๐‘ง). ๐‘‘(๐‘‡๐‘ง1, ๐‘ง1))๐œ† โ‰ค

๐‘‘(๐‘‡๐‘ง , ๐‘ง)๐œ†. ๐‘‘(๐‘‡๐‘ง 1, ๐‘ง1)๐œ†

By lemma 2.12 , z = z1 .This Completes the proof.

Theorem 3.2 Let (X, d) be a complete multiplicative cone b- metric space with power

๐‘  โ‰ฅ 1. Suppose the mapping ๐‘‡: ๐‘‹ โ†’ ๐‘‹ holds the contractive condition,

๐‘‘ ๐‘‡๐‘ฅ, ๐‘‡๐‘ฆ โ‰ค ๐‘‘ ๐‘‡๐‘ฅ, ๐‘ฆ . ๐‘‘ ๐‘‡๐‘ฆ, ๐‘ฅ ๐œ†,

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where ๐œ† โˆˆ [0,12) is a constant. Then T has a unique fixed point in X. And for any

๐‘ฅ โˆˆ ๐‘‹, iterative sequence (๐‘‡๐‘›๐‘ฅ) converges to the fixed point.

Proof. Choose ๐‘ฅ0โˆˆ ๐‘‹. Set ๐‘ฅ1= ๐‘‡๐‘ฅ0, ๐‘ฅ2= ๐‘‡๐‘ฅ1=

๐‘‡2๐‘ฅ

0,..., ๐‘ฅ๐‘›+1= ๐‘‡๐‘ฅ๐‘›= ๐‘‡๐‘›+1๐‘ฅ0,...

we have

๐‘‘ ๐‘ฅ๐‘›+1, ๐‘ฅ๐‘› = ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘›โˆ’1

โ‰ค ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1 . ๐‘‘ ๐‘‡๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘› )๐œ†

โ‰ค ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1 . ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘› )๐œ† โ‰ค ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1 ๐œ†

... ... โ‰ค ๐‘‘(๐‘ฅ1 , ๐‘ฅ0)๐œ†๐‘› For n > m,

๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘š

โ‰ค (๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1 . ๐‘‘ ๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›โˆ’2 โ€ฆ ๐‘‘ ๐‘ฅ๐‘š +1, ๐‘ฅ๐‘š )๐‘  โ‰ค

(๐‘‘(๐‘ฅ1, ๐‘ฅ0)๐œ†๐‘› โˆ’1+๐œ†๐‘› โˆ’2+โ‹ฏ+๐œ†๐‘š)๐‘  โ‰ค (๐‘‘(๐‘ฅ1, ๐‘ฅ0)

๐œ† ๐‘š

1โˆ’๐œ†

โ‰ค ๐‘‘(๐‘ฅ1, ๐‘ฅ0) ๐‘ ๐œ†๐‘š

1โˆ’๐‘ ๐œ†

This implies ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘š โ†’ 1 ๐‘›, ๐‘š โ†’โˆž . (i.e) ๐‘‘(๐‘ฅ1, ๐‘ฅ0)

๐‘ ๐œ† ๐‘š

1โˆ’๐‘ ๐œ† โ†’ 1 as mโ†’โˆž for any ๐‘  โ‰ฅ 1.

Hence {๐‘ฅ๐‘›} is a Cauchy sequence. Since (X,d) is a Complete multiplicative Cone b-metric space, there is ๐‘ง โˆˆ ๐‘‹ such that ๐‘ฅ๐‘› โ†’ ๐‘ง ๐‘› โ†’โˆž for all n > n0 .

d(Tz,z) โ‰ค (๐‘‘ ๐‘‡๐‘ง, ๐‘‡๐‘ฅ๐‘› . ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘ง )๐‘ 

โ‰ค

(๐‘‘ ๐‘‡๐‘ง, ๐‘ฅ๐‘› . ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘ง )๐‘ ๐œ†. ๐‘‘(๐‘ฅ๐‘›+1,๐‘ง)๐‘ 

โ‰ค

๐‘‘ ๐‘‡๐‘ง, ๐‘ง . ๐‘‘ ๐‘ฅ๐‘›, ๐‘ง ๐‘ 

. ๐‘‘ ๐‘ฅ๐‘›+1, ๐‘ง ๐‘ ๐œ†

๐‘‘ ๐‘ฅ๐‘›+1,๐‘ง ๐‘ 

โ‰ค ๐‘‘(๐‘ฅ๐‘›, ๐‘ง)๐‘ 2๐œ†๐‘‘ ๐‘ฅ๐‘›+1,., ๐‘ง ๐‘ ๐œ†

. ๐‘‘(๐‘ฅ๐‘›+1,๐‘ง)๐‘  we have, d(Tz,z) โ‰ค ๐‘‘(๐‘ฅ๐‘›+1,๐‘ง)

๐‘ 

1โˆ’๐‘ ๐œ† โ‰ช ๐‘ , for each

n > n0 , By use of lemma 2.14 ,we deduce that

๐‘‘ ๐‘‡๐‘ง, ๐‘ง = 1. This implies Tz = z. So z is a fixed point of T. For proving uniqueness, if there is another fixed point z1, then by the given assertion,

d(z, z1) = d(Tz,Tz1)

โ‰ค (๐‘‘(๐‘‡๐‘ง , ๐‘ง1). ๐‘‘(๐‘‡๐‘ง1, ๐‘ง))๐œ† โ‰ค

๐‘‘(๐‘‡๐‘ง , ๐‘ง1)๐œ†. ๐‘‘(๐‘‡๐‘ง1, ๐‘ง)๐œ†

By lemma 2.14 , z = z1 , This Completes the proof.

Theorem 3.3 Let (X, d) be a complete cone b- metric space with metric d and let ๐‘‡: ๐‘‹ โ†’ ๐‘‹ be a function with the following condition,

(4)

for all ๐‘ฅ, ๐‘ฆ โˆˆ ๐‘‹, where p, q, r are non- negative real numbers and satisfy ๐‘ + (๐‘ž + ๐‘Ÿ)๐‘ < 1 for ๐‘  โ‰ฅ 1. Then T has a unique fixed point.

Proof. Let ๐‘ฅ0โˆˆ ๐‘‹ and {๐‘ฅ๐‘›} be a sequence in X such that ๐‘ฅ๐‘›= ๐‘‡๐‘ฅ๐‘›โˆ’1= ๐‘‡๐‘›๐‘ฅ0.

Now, ๐‘‘ ๐‘ฅ๐‘›+1, ๐‘ฅ๐‘› = ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘›โˆ’1

โ‰ค ๐‘‘(๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘›)๐‘. ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›โˆ’1)๐‘ž. ๐‘‘(๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘›โˆ’1)๐‘Ÿ

โ‰ค

(๐‘‘(๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1). ๐‘‘(๐‘ฅ๐‘›+1, ๐‘‡๐‘ฅ๐‘›))๐‘ ๐‘. ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›โˆ’1)๐‘ž. ๐‘‘(๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1)๐‘Ÿ

โ‰ค ๐‘‘(๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1)๐‘ ๐‘. ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘ž+๐‘Ÿ

๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1 1โˆ’๐‘ ๐‘ โ‰ค ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘ž+๐‘Ÿ

---โ†’ (1)

secondly,

๐‘‘ ๐‘ฅ๐‘›+1, ๐‘ฅ๐‘› = ๐‘‘ ๐‘‡๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘›โˆ’1 =

๐‘‘ ๐‘‡๐‘ฅ๐‘› โˆ’1, ๐‘‡๐‘ฅ๐‘›

โ‰ค ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›โˆ’1)๐‘. ๐‘‘(๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘›)๐‘ž. ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›)๐‘Ÿ

โ‰ค

๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›โˆ’1)๐‘[๐‘‘ ๐‘ฅ๐‘›,๐‘ฅ๐‘›+1 . ๐‘‘(๐‘ฅ๐‘›+1,๐‘‡๐‘ฅ๐‘›)]๐‘ ๐‘ž ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›)๐‘Ÿ

โ‰ค ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘ ๐‘‘ ๐‘ฅ๐‘›,๐‘ฅ๐‘›+1 ๐‘ ๐‘ž

๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘‡๐‘ฅ๐‘›)๐‘Ÿ ๐‘‘ ๐‘ฅ๐‘›+1, ๐‘ฅ๐‘› 1โˆ’๐‘ ๐‘ž โ‰ค ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘+๐‘Ÿ

---โ†’ (2)

Multiplying (1) & (2)

๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1 1โˆ’๐‘ ๐‘ ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1 1โˆ’๐‘ ๐‘ž

โ‰ค ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘ž+๐‘Ÿ.๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘+๐‘Ÿ

๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1 2โˆ’๐‘  ๐‘+๐‘ž โ‰ค

๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)๐‘+๐‘ž +2๐‘Ÿ ๐‘‘(๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1) โ‰ค ๐‘‘(๐‘ฅ๐‘›โˆ’1, ๐‘ฅ๐‘›)

๐‘ +๐‘ž+2๐‘Ÿ 2โˆ’๐‘ (๐‘ +๐‘ž)

Put ๐œ† =2โˆ’๐‘ (๐‘+๐‘ž)๐‘+๐‘ž+2๐‘Ÿ, it is easy to see that ๐œ† โˆˆ [0,1). Thus,

๐‘‘(๐‘ฅ๐‘›, ๐‘ฅ๐‘›+1)โ‰ค ๐‘‘(๐‘ฅ๐‘›, ๐‘ฅ๐‘›โˆ’1)๐œ† . . . โ‰ค ๐‘‘(๐‘ฅ1, ๐‘ฅ0)๐œ†๐‘›

we can follow the same argument that is given in Theorem 3.1 [16 ] , there exist ๐‘ฅโˆ—โˆˆ ๐‘‹ such that

๐‘ฅ๐‘› โ†’๐‘ฅโˆ—. Let c >>1 be arbitrary. Since ๐‘ฅ๐‘› โ†’๐‘ฅโˆ—, there exist N such that

๐‘‘(๐‘ฅ๐‘›,๐‘ฅโˆ—) โ‰ค c

Next we show that ๐‘ฅโˆ— is fixed point of T, we have

๐‘‘ ๐‘‡๐‘ฅโˆ—, ๐‘ฅโˆ— = [๐‘‘ ๐‘‡๐‘ฅโˆ—, ๐‘‡๐‘ฅ

๐‘› . ๐‘‘ ๐‘‡๐‘ฅ๐‘› , ๐‘ฅโˆ— ]๐‘ 

โ‰ค ๐‘‘ ๐‘‡๐‘ฅโˆ—, ๐‘‡ ๐‘ฅ๐‘› ๐‘ . ๐‘‘ ๐‘ฅ๐‘›+1, ๐‘ฅโˆ— ๐‘ 

โ‰ค [๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘. ๐‘‘ ๐‘ฅ

๐‘›, ๐‘‡๐‘ฅ๐‘› ๐‘ž. ๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ๐‘› ๐‘Ÿ]๐‘ .

๐‘‘(๐‘ฅ๐‘›+1, ๐‘ฅโˆ—)๐‘  โ‰ค

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘ ๐‘. [๐‘‘ ๐‘ฅ

๐‘›, ๐‘ฅโˆ— . ๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅ๐‘›)]๐‘ 2๐‘ž.

๐‘‘(๐‘ฅโˆ—, ๐‘ฅ

๐‘›)๐‘ ๐‘Ÿ๐‘‘(๐‘ฅ๐‘›+1, ๐‘ฅโˆ—)๐‘ 

โ‰ค

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘ ๐‘. ๐‘‘ ๐‘ฅ

๐‘›, ๐‘ฅโˆ— ๐‘ 2๐‘ž. ๐‘‘(๐‘ฅโˆ—, ๐‘ฅ๐‘›+1)๐‘ 2๐‘ž.

๐‘‘(๐‘ฅโˆ—, ๐‘ฅ

๐‘›)๐‘ ๐‘Ÿ๐‘‘(๐‘ฅ๐‘›+1, ๐‘ฅโˆ—)๐‘  ๐‘‘ ๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ— . ๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)โˆ’๐‘ ๐‘

= ๐‘‘ ๐‘ฅ๐‘› ,๐‘ฅโˆ— ๐‘ ๐‘Ÿ+๐‘ 2๐‘ž

. ๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ ๐‘›+1 ๐‘ 

2๐‘+๐‘Ÿ๐‘ 

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)1โˆ’๐‘ ๐‘ โ‰ค

๐‘‘ ๐‘ฅ๐‘› , ๐‘ฅโˆ— ๐‘ ๐‘Ÿ+๐‘ 

2๐‘ž

. ๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ ๐‘›+1 ๐‘ 

2๐‘ž+๐‘  ... (3)

On the Other hand ,

d(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—) = [d(๐‘ฅโˆ— , ๐‘‡๐‘ฅ๐‘›) . d(๐‘‡๐‘ฅ๐‘› , ๐‘‡๐‘ฅโˆ—)] ๐‘  = d(๐‘ฅโˆ— , ๐‘ฅ๐‘›+1)๐‘  . d(๐‘‡๐‘ฅ๐‘› , ๐‘‡๐‘ฅโˆ—) ๐‘ 

โ‰ค ๐‘‘(๐‘ฅโˆ—, ๐‘ฅ

๐‘›+1)๐‘ . [๐‘‘ ๐‘ฅ๐‘›, ๐‘‡๐‘ฅ๐‘› ๐‘. ๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘ž. ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅโˆ— ๐‘Ÿ]๐‘ 

โ‰ค ๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ

๐‘›+1 ๐‘ . [๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅโˆ— . ๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅ๐‘›)]๐‘ 2๐‘.

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘ ๐‘ž. ๐‘‘(๐‘ฅ ๐‘›, ๐‘ฅโˆ—)๐‘Ÿ๐‘ 

โ‰ค ๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ

๐‘›+1 ๐‘ . ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅโˆ— ๐‘ 2๐‘. ๐‘‘(๐‘ฅโˆ—, ๐‘ฅ๐‘›+1)๐‘ 2๐‘.

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘ ๐‘ž. ๐‘‘(๐‘ฅ ๐‘›, ๐‘ฅโˆ—)๐‘Ÿ๐‘ 

๐‘‘ ๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ— . ๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)โˆ’๐‘ ๐‘ž =

๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ ๐‘›+1 ๐‘ +๐‘ 

2๐‘

. ๐‘‘ ๐‘ฅ๐‘›, ๐‘ฅโˆ—, ๐‘ 

2๐‘+๐‘Ÿ๐‘ 

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)1โˆ’๐‘ ๐‘ž โ‰ค

๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ ๐‘›+1

๐‘ +๐‘ 2๐‘

. ๐‘‘ , ๐‘ฅ๐‘› ,๐‘ฅโˆ— ๐‘ 2๐‘+๐‘Ÿ๐‘ 

...(4)

Multiplying (3) & (4) gives ,

๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)2โˆ’๐‘ ๐‘ โˆ’๐‘ ๐‘ž โ‰ค

๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ ๐‘›+1 ๐‘ +๐‘ 

2๐‘+๐‘ +๐‘ 2๐‘ž

. ๐‘‘ , ๐‘ฅ๐‘› ,๐‘ฅโˆ—

๐‘ 2๐‘+๐‘Ÿ๐‘ +๐‘ ๐‘Ÿ +๐‘ 2๐‘ž

โ‰ค ๐‘‘ ๐‘ฅโˆ—, ๐‘ฅ

๐‘›+1 2๐‘ +๐‘ 2(๐‘+๐‘ž). ๐‘‘ , ๐‘ฅ๐‘› ,๐‘ฅโˆ—

2๐‘Ÿ๐‘ +๐‘ 2(๐‘+๐‘ž)

d(๐‘ฅโˆ— , ๐‘‡๐‘ฅโˆ—) โ‰ค c

we can see from lemma 2.14, that d(๐‘ฅโˆ— , ๐‘‡๐‘ฅโˆ—) = 1. (ie) the mapping T has a fixed point ๐‘ฅโˆ— . At last, for uniqueness, if there is another fixed point ๐‘ฆโˆ— then d(๐‘ฅโˆ—, ๐‘ฆโˆ—) = d(T๐‘ฅโˆ—,๐‘‡๐‘ฆโˆ—)

โ‰ค ๐‘‘(๐‘ฅโˆ—, ๐‘‡๐‘ฅโˆ—)๐‘

๐‘‘(๐‘ฆโˆ—, ๐‘‡๐‘ฆโˆ—)๐‘ž๐‘‘(๐‘ฅโˆ—, ๐‘ฆโˆ—)๐‘Ÿ

โŸน ๐‘‘(๐‘ฅ, ๐‘ฆ) โ‰ค๐‘‘(๐‘ฅโˆ—, ๐‘ฆโˆ—)๐‘Ÿ.

Owing to 0โ‰ค ๐‘Ÿ < 1 , we deduce from lemma 2.14 that ๐‘ฅโˆ— = ๐‘ฆโˆ— . This completes the Proof.

4. References

[1] S. Banach, Sur les operations dans les ensembles abstrait

(5)

[2] I. A. Bakhtin, The contraction mapping principle in almost metric spaces, Func. Anal., Gos. Ped. Inst. Unianowsk, Vol. 30, 1989, pp. 26โ€“37.

[3] A. E. Bashirov, E.M. Kurpinar, A.

ยจOzyapici,Multiplicative calculus and its applications, J.

Math.Analy. App., 337, 2008, pp. 36โ€“48.

[4] S. Cezerwik, Contraction mappings in b-metric spaces,

Acta Mathematica et informatica Universitatis Ost. Vol.1, 1993 pp. 5-11.

[5] K. Deimling, Nonlinerar Functional Analysis, Springer,

1985.

[6] Kannan .R.Some results on fixed points .Bull.Calcutta Math.Soc.60.71-76(1968).

[7] Kannan .R. Some results on fixed points ,II am.Math.Mon 75,405 -408 (1969).

[8] R. George, H. Nabwey, K. P. Reshma, R. Rajagopalan, Generalized cone b-metric spaces and contraction principle, Mathematykn Behhnk, 2015.

[9] L. G. Haung, X. Zhang, Cone metric space and fixed point

theorems of contractive mappings, J. Math. Anal., Apal,

Vol. 332(2), 2007, pp. 1468โ€“1476.

[10] N. Hussain, M. H. Shah, KKM mappings in cone b-metric

spaces, Comput. Math. Appl., Vol. 62, 2011, pp. 1677โ€“ 1684.

[11] H. Huaping, X. Shaoyuan, Fixed point theorems of

contractive mapping in cone b-metric spaces and applications, Fixed Point Theory Appl., 2013 2013:112.

[12] H. Hxiaoju , M. Song, D. Chen, Common fixed points for

weak commutative mappings on a multiplicative metric space, Fixed Point Theory and Applications 2014, 2014:48.

[13] M. Ozavsar, A. C. Cevikel, Fixed point of multiplicative contraction mappings on multiplicative metric space, arXiv:1205.5131v1 [matn.GN] (2012).

[14] Shyam Lal Singh, Stephen Czerwik and Krzysztof Krol, ' Coincidences and fixed points of hybrid contractions', Tamsui Oxford Journal of Mathematical Sciences 24(2008), no. 4, 401 - 416.

[15] Pankaj Kumar Mishra, Shweta Sachdeva, Banerjee, ' Some

fixed point theorems in b- metruc spaces', Turkish Journal of Analysis and Number theory, 2014, Vol.2, No. 1, 19 - 22.

[16] Akbar Zada, Rahim Shah and Shahid Saifullah, ' Some

References

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