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International Journal of Mathematical Archive-9(3), 2018,

107-112

Available online throug

ISSN 2229 – 5046

International Journal of Mathematical Archive- 9(3), March – 2018 107 CONFERENCE PAPER

National Conference dated 26th Feb. 2018, on β€œNew Trends in Mathematical Modelling” (NTMM - 2018),

Organized by Sri Sarada College for Women, Salem, Tamil Nadu, India.

(

𝟏

,

𝜢

)

βˆ’

DERIVATIONS IN

πšͺ βˆ’

NEAR RING

L. MADHUCHELVI

1

AND B. DHIVYA

2

1Associate Professor, Department of Mathematics, Sri Sarada College for Women (Autonomous) Salem-16, India.

2Research Scholar, Department of Mathematics, Sri Sarada College for Women (Autonomous) Salem-16, India.

E-mail: [email protected]1 and [email protected]2.

ABSTRACT

In this paper, we introduce the notion of

(1,𝛼)- derivation of 𝛀 βˆ’ near ring and give some generalizations of [1]. The purpose of this paper is to prove the following two assertions: (i) Let Mbe a semiprime𝛀 βˆ’ near ring, U be a subset of M such that 0∈ π‘ˆ,π‘ˆπ›€π‘€ βŠ† π‘ˆ and 𝑑 be a (1,𝛼)-derivation of M. If 𝑑 acts as homomorphism on U or as antihomomorphism on U under certain conditions on𝛼, then 𝑑(π‘ˆ) = {0}. (ii) Let M be a prime 𝛀 βˆ’ near ring, U be a nonzero semigroup ideal of M, and 𝑑 be a(1,𝛼)derivation on M. If 𝑑(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦) = 0 for all π‘₯,𝑦 ∈ π‘ˆ, then (𝑀, +) is abelian.

Key words: prime 𝛀 βˆ’ near ring, semiprime 𝛀 βˆ’ near ring, semigroup ideal,(1,𝛼)βˆ’ derivation.

2000 Mathematics subject classification: 16Y30, 16Y99.

1. INTRODUCTION

The notion of a Ξ“ βˆ’ring a concept more general than a ring was defined by Nobusawa [6]. As a generalization of near rings,Ξ“ βˆ’ near ring introduced by Satyanarayana [7]. The derivationsin Ξ“ βˆ’near rings has been introduced by Bell and Mason [3].They obtained some basic properties of derivations in, Ξ“ βˆ’near ring. In [2] Argac defined a two sided 𝛼 βˆ’ derivation of aΞ“ βˆ’ near ring. In a similar way, we introduce the notion of a of (1,𝛼) βˆ’ derivation of Ξ“ βˆ’nearring and give some Generalizations of [1, 2].

2. PRELIMINARIES

Throughout this paper, 𝑀 stands for a zero symmetric rightΞ“ βˆ’ near ring. In this section, we collect all basic concepts and results in Ξ“ βˆ’ near rings mostly from Mustafa Kazaz and Akin Alkan [5] which are required for our study.

Definition 2.1[5]: A πšͺ βˆ’ near ring𝑀 is a triple (𝑀, +,Ξ“), where (i) (𝑀, +)is a group (not necessarily abelian),

(ii) Ξ“is a non empty set of binary operations on 𝑀 such that (𝑀, +,Ξ³) is a near ring for each 𝛾 ∈ Ξ“. (iii)(xΞ²y)Ξ³z = xΞ²(yΞ³z)for all π‘₯,𝑦,𝑧 ∈ 𝑀 and 𝛽,𝛾 ∈ Ξ“

Definition 2.2[5]: A Ξ“ βˆ’ near ring 𝑀 is said to be zero-symmetricΞ“ βˆ’ near ring if 0𝛾π‘₯= 0 for all π‘₯ ∈ 𝑀and 𝛾 ∈ Ξ“.

Definition 2.3[5]: A Ξ“ βˆ’ near ring 𝑀 is said to be prime πšͺ βˆ’ near ring if π‘₯Γ𝑀Γ𝑦= {0} for π‘₯,𝑦 ∈ 𝑀impliesπ‘₯= 0 or

𝑦= 0 and semiprimeπšͺ βˆ’ near ring if π‘₯Γ𝑀Γπ‘₯= {0} forπ‘₯ ∈ 𝑀implies = 0 .

Definition 2.4[4]: A derivation on 𝑀 is defined to be an additive endomorphism 𝑑 of 𝑀 satisfying the product rule

𝑑(π‘₯𝛾𝑦) =𝑑(π‘₯)𝛾𝑦+π‘₯𝛾𝑑(𝑦)for all π‘₯,𝑦 ∈ 𝑀 and 𝛾 ∈ Ξ“, or equivalently

(2)

Definition 2.5[5]: If 𝑀 and 𝑀′ are two Ξ“ βˆ’ near rings, then a mapping𝑓:𝑀 β†’ 𝑀′ such that𝑓(π‘₯+𝑦) =𝑓(π‘₯) +𝑓(𝑦) and 𝑓(π‘₯𝛾𝑦) =𝑓(π‘₯)𝛾𝑓(𝑦) (resp.𝑓(π‘₯𝛾𝑦) =𝑓(𝑦)𝛾𝑓(π‘₯)) for all π‘₯,𝑦 ∈ 𝑀and 𝛾 ∈ Ξ“, is called a Ξ“ βˆ’ near rings homomorphism (resp.an anti- homomorphism) on 𝑀.

Definition 2.6[5]: Let𝑆 be a nonempty subset of 𝑀 and let 𝑑 be a derivation on 𝑀.

If 𝑑(π‘₯𝛾𝑦) =𝑑(π‘₯)𝛾𝑑(𝑦)(resp.𝑑(π‘₯𝛾𝑦) =𝑑(𝑦)𝛾𝑑(π‘₯)) for all π‘₯,𝑦 ∈ 𝑆 and 𝛾 ∈ Ξ“, then 𝑑 is said to act as a homomorphism (resp.an anti-homomorphism) on 𝑆.

Definition 2.7[5]: An additive endomorphism 𝑑: 𝑀 β†’ 𝑀 of a Ξ“ βˆ’ near ring 𝑀 is called a (𝛼,𝛽)derivation on 𝑀 if there exist two functions 𝛼,𝛽:𝑀 β†’ 𝑀 such that the following product rule holds:𝑑(π‘₯𝛾𝑦) =𝑑(π‘₯)𝛾𝛼(𝑦) +𝛽(π‘₯)𝛾𝑑(𝑦)forall

π‘₯,𝑦 ∈ 𝑀 and 𝛾 ∈ Ξ“.One can easily show that if 𝑑 is(𝛼,𝛽)derivation on 𝑀 Such that

𝛼(π‘₯+𝑦) =𝛼(π‘₯) +𝛼(𝑦)and 𝛽(π‘₯+𝑦) =𝛽(π‘₯) +𝛽(𝑦), then 𝑑(π‘₯𝛾𝑦) =𝛽(π‘₯)𝛾𝑑(𝑦) +𝑑(π‘₯)𝛾𝛼(𝑦).

Definition 2.8[5]: An additive mapping 𝑑: 𝑀 β†’ 𝑀 is called a two-sided 𝛼 βˆ’ derivation if 𝑑 is (𝛼, 1)derivation as well as(1,𝛼)-derivation. we should note that if 𝛼= 1,then a two sided𝛼 βˆ’ derivation is just a derivation .

Definition 2.9 [4]: A nonempty subset π‘ˆ of M is called a semigroup right ideal (resp. semigroup left ideal) if

π‘ˆΞ“π‘€ βŠ‚ 𝑀(π‘€Ξ“π‘ˆ) is called semigroup ideal if it is both right and left semigroup ideal.

3. (𝟏,𝜢)- derivation in prime and semiprime πšͺ βˆ’ near rings

We need the following Lemmas to prove the main theorem of this section.

Lemma 3.1: Let 𝑀 be a prime Ξ“ βˆ’ near ring and let π‘ˆ be a nonzero semigroup ideal of 𝑀. If π‘Ž+𝑏=𝑏+π‘Ž for all

π‘Ž,𝑏 ∈ π‘ˆ,then(𝑀, +) is abelian.

Proof∢ By the hypothesis, we have π‘₯π›Ύπ‘Ž+π‘¦π›Ύπ‘Ž βˆ’ π‘₯π›Ύπ‘Ž βˆ’ π‘¦π›Ύπ‘Ž= 0 for all π‘Ž ∈ π‘ˆ, π‘₯,𝑦 ∈ 𝑀 and 𝛾 ∈ Ξ“.Then we get

(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)π›Ύπ‘Ž= 0 for all π‘Ž ∈ π‘ˆ, π‘₯,𝑦 ∈ 𝑀 and 𝛾 ∈ Ξ“. It means that (π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)Ξ“MΞ“UβŠ†(π‘₯+𝑦 βˆ’ π‘₯ βˆ’

𝑦ΓU=0.

Since π‘ˆ is a non zerosemigroup ideal thenπ‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦= 0 for all π‘₯,𝑦 ∈ 𝑀 by the primeness of 𝑀. Thus (𝑀, +) is Abelian.

Lemma 3.2: Let 𝑀 be right Ξ“ βˆ’ near ring, 𝑑 a(1,𝛼)- derivation of 𝑀 and π‘ˆ a multiplicative semigroup of 𝑀 which contains 0. If 𝑑 acts as an anti-homomorphism onπ‘ˆ and 𝛼(π‘₯) =π‘₯, then π‘₯𝛾0 = 0 for all π‘₯ ∈ π‘ˆ.

Proof: Since 0𝛾π‘₯= 0 for all π‘₯ ∈ π‘ˆ and 𝛾 ∈ Ξ“,𝑑acts as an anti-homomorphism on π‘ˆ, it is clear that 𝑑(0𝛾π‘₯) =

𝑑(π‘₯)𝛾𝑑(0) =𝑑(π‘₯)𝛾0 for all π‘₯ ∈ π‘ˆ. Taking π‘₯𝛾0 instead of π‘₯ one, can obtain𝑑(π‘₯)𝛾0 +𝛼(π‘₯)𝛾𝑑(0) = 𝛼(π‘₯)𝛾𝑑(0) = 0 for all π‘₯ ∈ π‘ˆ. Thus we have π‘₯𝛾0 = 0 for all π‘₯ ∈ π‘ˆ.

Lemma 3.3: Let 𝑀 be a Ξ“ βˆ’ near ring and π‘ˆbe a multiplicative subsemigroup of 𝑀. If 𝑑 is a (1,𝛼)βˆ’ derivation of𝑀 such that 𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦) for all π‘₯,𝑦 ∈Uand 𝛼(U) = U, thenπ‘›πœ‡(𝑑(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦)) =π‘›πœ‡π‘‘(π‘₯)𝛾𝑦+

π‘›πœ‡π›Ό(π‘₯)𝛾𝑑(𝑦) for all 𝑛,π‘₯,𝑦 ∈U, 𝛾,πœ‡ ∈ Ξ“.

Proof: Since 𝑑(π‘₯𝛾𝑦) =𝑑(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦).From the associative lawπ‘‘οΏ½π‘›πœ‡(π‘₯𝛾𝑦)οΏ½=𝑑(𝑛)πœ‡(π‘₯𝛾𝑦) +𝛼(𝑛)πœ‡π‘‘(π‘₯𝛾𝑦) =𝑑(𝑛)πœ‡(π‘₯𝛾𝑦) +𝛼(𝑛)πœ‡οΏ½π‘‘(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦)οΏ½ since (U) = U , we have

π‘‘οΏ½π‘›πœ‡(π‘₯𝛾𝑦)οΏ½= 𝑑(𝑛)πœ‡(π‘₯𝛾𝑦) +π‘›πœ‡οΏ½π‘‘(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦)οΏ½ (1)

On other hand for all 𝑛,π‘₯,𝑦 ∈ π‘ˆ and 𝛾,ΞΌ ∈ Ξ“.

𝑑�(π‘›πœ‡π‘₯)𝛾𝑦�=𝑑(π‘›πœ‡π‘₯)𝛾𝑦+𝛼(π‘›πœ‡π‘₯)𝛾𝑑(𝑦)

=𝑑(𝑛)πœ‡(π‘₯𝛾𝑦) +𝛼(𝑛)πœ‡οΏ½π‘‘(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦)οΏ½

=𝑑(𝑛)πœ‡(π‘₯𝛾𝑦) +π‘›πœ‡(𝑑(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦))since𝛼(U) = U (2)

Since Uis a semigroup ideal, comparing (1) and (2)

π‘›πœ‡(𝑑(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦) = π‘›πœ‡π‘‘(π‘₯)𝛾𝑦+π‘›πœ‡π›Ό(π‘₯)𝛾𝑑(𝑦)

Lemma 3.4: Let 𝑀 be a prime Ξ“ βˆ’ near ring and π‘ˆ be a non zero semigroup ideal of 𝑀. Let 𝑑 be a non-zero (1,𝛼) derivation on 𝑀 such that 𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦)for all π‘₯,𝑦 ∈ π‘ˆ,𝛾 ∈ Ξ“. If π‘₯ ∈ 𝑀 and 𝑑(π‘ˆ)𝛾π‘₯= {0} then π‘₯= 0.

Proof: Assume that 𝑑(π‘ˆ)𝛾π‘₯= {0}. Since U is a non-zero semigroupideal of 𝑀,𝑑(π‘’πœ‡π‘¦)𝛾π‘₯= 0 for all π‘₯,𝑦 ∈ 𝑀,𝑒 ∈

π‘ˆand 𝛾,πœ‡ ∈ Ξ“. Hence0 = [𝑑(𝑒)πœ‡π‘¦+𝛼(𝑒)πœ‡π‘‘(𝑦)]𝛾π‘₯= 𝛼(𝑒)πœ‡π‘‘(𝑦)𝛾π‘₯ for all 𝑒 ∈ π‘ˆ,𝑦 ∈ 𝑀.β‡’ 𝛼(𝑒)Γ𝑑(𝑦)Ξ“π‘₯= 0 for

all 𝛾,ΞΌ ∈ Ξ“. Since 𝑀 is prime,𝛼(𝑒) = 0or π‘₯= 0. If𝛼(𝑒) = 0 for all 𝑒 ∈ π‘ˆ, then𝛼= 0. This is not possible. There for

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Lemma 3.5: Let 𝑀 be a prime Ξ“ βˆ’ near ring and π‘ˆ be a non zero semigroup ideal of 𝑀 and a non-zero

(1,𝛼)βˆ’ derivation on 𝑀.If 𝑑(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦) = 0 for allπ‘₯,𝑦 ∈ π‘ˆthen 𝛼(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)𝛾𝑑(𝑧) = 0 for allπ‘₯,𝑦 ∈ π‘ˆ

and 𝑧 ∈ 𝑀.

Proof: Assume that 𝑑(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦) = 0 for allπ‘₯,𝑦 ∈ π‘ˆ.Let us take 𝑦𝛾𝑧 and π‘₯𝛾𝑧 instead of 𝑦 andπ‘₯ respectively (where 𝑍 ∈ 𝑀 and 𝛾 ∈ Ξ“) We obtain

𝑑(π‘₯𝛾𝑧+𝑦𝛾𝑧 βˆ’ π‘₯𝛾𝑧 βˆ’ 𝑦𝛾𝑧) =𝑑�(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)𝛾𝑧�= 0

β‡’ 𝑑(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)𝛾𝑧+𝛼(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)𝛾𝑑(𝑧) = 𝛼(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)𝛾𝑑(𝑧) = 0 for all π‘₯,𝑦 ∈ π‘ˆ,𝑧 ∈ 𝑀, 𝛾 ∈ Ξ“.

Therefore 𝛼(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)Γ𝑑(𝑧) = 0 𝑓or all 𝛾 ∈ Ξ“.

Lemma 3.6: Let 𝑀 be a Ξ“ βˆ’ near ring π‘ˆ be a multiplicative subsemigroup of𝑀. Let 𝑑 be (1,𝛼)- derivation of 𝑀 such That 𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦) for all π‘₯,𝑦 ∈ π‘ˆ and 𝛼(π‘ˆ) =π‘ˆ.

(i) If 𝑑 acts as a homomorphism on π‘ˆ then,

𝑑(𝑦)ΞΌπ‘₯γ𝑑(𝑦) =𝛼(𝑦)ΞΌπ‘₯γ𝑑(𝑦) =𝑑(𝑦)ΞΌπ‘₯γ𝑦 for all π‘₯,𝑦 ∈ π‘ˆ andπœ‡,𝛾 ∈ Ξ“. (ii) If 𝑑 acts as a anti- homomorphism onπ‘ˆ then,

𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦) =π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦) =𝑑(𝑦)𝛾𝑦𝛾π‘₯for all π‘₯,𝑦 ∈ π‘ˆandπœ‡,𝛾 ∈ Ξ“.

Proof:

(i)Let 𝑑 acts as a homomorphism on π‘ˆ. Then

𝑑(π‘₯𝛾𝑦) =𝑑(π‘₯)𝛾𝑦+ 𝛼(π‘₯)𝛾𝑑(𝑦) =𝑑(π‘¦πœ‡π‘₯𝛾𝑦)for all π‘₯,𝑦 ∈ π‘ˆ,𝛾 ∈ Ξ“ (3)

Substituting π‘¦πœ‡π‘₯ for π‘₯ in equation (3)

𝑑(π‘¦πœ‡π‘₯𝛾𝑦) =𝑑(π‘¦πœ‡π‘₯)𝛾𝑦+𝛼(π‘¦πœ‡π‘₯)𝛾𝑑(𝑦) =𝑑(𝑦)πœ‡π‘‘(π‘₯𝛾𝑦)for all π‘₯,𝑦 ∈ π‘ˆπœ‡,𝛾 ∈ Ξ“ (4)

By the Lemma3.3

𝑑(𝑦)πœ‡π‘‘(π‘₯𝛾𝑦) =𝑑(𝑦)πœ‡π‘‘(π‘₯)𝛾𝑦+𝑑(𝑦)πœ‡π›Ό(π‘₯)𝛾𝑑(𝑦)for all π‘₯,𝑦 ∈ π‘ˆ,πœ‡,𝛾 ∈ Ξ“.

Using this relation in equation (4), we get

𝛼(𝑦)πœ‡π›Ό(π‘₯)𝛾𝑑(𝑦) = 𝑑(𝑦)πœ‡π›Ό(π‘₯)𝛾𝑑(𝑦)

Since 𝛼(π‘ˆ) =π‘ˆ ,we have

𝛼(𝑦)πœ‡π‘₯𝛾𝑑(𝑦) = 𝑑(𝑦)πœ‡π‘₯𝛾𝑑(𝑦)for all π‘₯,𝑦 ∈ π‘ˆ,πœ‡,𝛾 ∈ Ξ“ .

Similarly taking π‘¦πœ‡π‘₯ instead of 𝑦in equation (3) we obtain

𝑑(π‘₯)𝛾𝑑(π‘¦πœ‡π‘₯) = 𝑑(π‘₯)π›Ύπ‘¦πœ‡π‘₯+𝛼(π‘₯)𝛾𝑑(π‘¦πœ‡π‘₯) =𝑑(π‘₯𝛾𝑦)πœ‡π‘‘(π‘₯)for all π‘₯,𝑦 ∈ π‘ˆ,πœ‡,𝛾 ∈ Ξ“ . (5)

On the other hand 𝑑(π‘₯𝛾𝑦)πœ‡π‘‘(π‘₯) =�𝑑(π‘₯)𝛾𝑦+𝛼(π‘₯)𝛾𝑑(𝑦)οΏ½πœ‡π‘‘(π‘₯) =𝑑(π‘₯)π›Ύπ‘¦πœ‡π‘₯+𝛼(π‘₯)𝛾𝑑(𝑦)πœ‡π‘‘(π‘₯). using this relation in (5) we get 𝑑(𝑦)πœ‡π‘₯𝛾𝑑(𝑦) =𝛼(𝑦)πœ‡π‘₯𝛾𝑑(𝑦) =𝑑(𝑦)πœ‡π‘₯𝛾𝑦 for all π‘₯,𝑦 ∈ π‘ˆ,πœ‡,𝛾 ∈ Ξ“

(ii) since𝑑 acts as a anti- homomorphism onπ‘ˆ,we have

𝑑(π‘₯𝛾𝑦) =𝑑(π‘₯)𝛾𝑦+ 𝛼(π‘₯)𝛾𝑑(𝑦)

β‡’ 𝑑(𝑦)𝛾𝑑(π‘₯) = 𝑑(π‘₯)𝛾𝑦+ 𝛼(π‘₯)𝛾𝑑(𝑦) for all π‘₯,𝑦 ∈ π‘ˆ,𝛾 ∈ Ξ“ (6)

Taking π‘₯𝛾𝑦 for 𝑦 in equation (6) and by the hypothesis we get

𝑑(π‘₯𝛾𝑦)𝛾𝑑(π‘₯) = 𝑑(π‘₯)𝛾π‘₯𝛾𝑦+ 𝛼(π‘₯)𝛾𝑑(π‘₯𝛾𝑦)

β‡’ 𝑑(π‘₯)𝛾𝑦𝛾𝑑(π‘₯) = 𝑑(π‘₯)𝛾π‘₯𝛾𝑦 (7)

Similarly takingπ‘₯𝛾𝑦 instead of π‘₯ in equation (6) and by hypothesis

𝑑(𝑦)𝛾𝑑(π‘₯𝛾𝑦) = 𝑑(π‘₯𝛾𝑦)𝛾𝑦+ 𝛼(π‘₯𝛾𝑦)𝛾𝑑(𝑦) β‡’ 𝑑(𝑦)𝛾𝛼(π‘₯)𝛾𝑑(𝑦) =𝛼(π‘₯𝛾𝑦)𝛾𝑑(𝑦)

Since 𝛼(π‘ˆ) =π‘ˆ, we have

𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦) =π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦)

Theorem 3.7: Let 𝑀 be a semiprime Ξ“ βˆ’ near ring and π‘ˆ be a subset of 𝑀 such that 0∈ π‘ˆand π‘ˆΞ“π‘€ βŠ† π‘ˆ. Let 𝑑 be a (1,𝛼)βˆ’ derivation on 𝑀 such that 𝛼(π‘ˆ) =π‘ˆ and 𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦) βˆ€π‘₯,𝑦 ∈ π‘ˆ

(i) If 𝑑acts as an homomorphism on π‘ˆthen 𝑑(π‘ˆ) = {0}

(ii) If𝑑acts as an anti- homomorphism on π‘ˆand 𝛼(0) = 0then 𝑑(π‘ˆ) = {0}

Proof: Suppose 𝑑acts as an homomorphism on π‘ˆ. By the Lemma 3.6, we have

(4)

Multiply (8) by 𝑑(𝑧) where 𝑧 ∈ π‘ˆ and using the hypothesis that 𝑑act as an homomorphism on π‘ˆ together with Lemma 3.6 we get

𝑑(𝑦)πœ‡π‘₯𝛾(𝑑(𝑦)πœ‡π‘§+𝛼(𝑦)πœ‡π‘‘(𝑧)) =𝑑(𝑦)πœ‡π‘₯π›Ύπ‘¦πœ‡π‘‘(𝑧)

β‡’ 𝑑(𝑦)πœ‡π‘₯𝛾𝑑(𝑦)πœ‡π‘§+ 𝑑(𝑦)πœ‡π‘₯𝛾𝛼(𝑦)πœ‡π‘‘(𝑧) = 𝑑(𝑦)πœ‡π‘₯π›Ύπ‘¦πœ‡π‘‘(𝑧) by the Lemma 3.3

Since 𝛼(π‘ˆ) =π‘ˆ, we get

𝑑(𝑦)πœ‡π‘₯𝛾𝑑(𝑦)πœ‡π‘§+ 𝑑(𝑦)πœ‡π‘₯π›Ύπ‘¦πœ‡π‘‘(𝑧) = 𝑑(𝑦)πœ‡π‘₯π›Ύπ‘¦πœ‡π‘‘(𝑧)

β‡’ 𝑑(𝑦)πœ‡π‘₯𝛾𝑑(𝑦)πœ‡π‘§= 0 for all π‘₯,𝑦 ∈ π‘ˆ and πœ‡,𝛾 ∈ Ξ“ (9)

Taking π‘§πœ‚π‘š instead of π‘₯ where π‘š ∈ 𝑀

We ge𝑑𝑑(𝑦)πœ‡π‘§πœ‚π‘šπ›Ύπ‘‘(𝑦)πœ‡π‘§= 0 for all π‘₯,𝑦,𝑧 ∈ π‘ˆ,π‘š ∈ 𝑀 and πœ‡,πœ‚,𝛾 ∈ Ξ“. ,

In particular

β‡’ 𝑑(𝑦)πœ‡π‘§Ξ“π‘€Ξ“π‘‘(𝑦)πœ‡π‘§= 0

By the semiprimeness of 𝑀 we conclude that

𝑑(𝑦)πœ‡π‘§= {0} (10)

Substitute π‘¦πœ‚π‘›for 𝑦 in equation (10)

𝑑(π‘¦πœ‚π‘›)πœ‡π‘§= 0 (11)

Left multiply (11) by 𝑑(𝑧)where 𝑧 ∈ π‘ˆ, we get

𝑑(𝑧)𝛽𝑑(π‘¦πœ‚π‘›)πœ‡π‘§= 0

β‡’ 𝑑(𝑧)𝛽𝑑(𝑦)πœ‚π‘›πœ‡π‘§+𝑑(𝑧)𝛽𝛼(𝑦)πœ‚π‘‘(𝑛)πœ‡π‘§= 0 by the Lemma 3.3

Since the second summand is zero by (11) we get

𝑑(𝑧)𝛽𝑑(𝑦)πœ‚π‘›πœ‡π‘§= 0

By the hypothesis and by using (10)

𝛼(𝑧)𝛽𝑑(𝑦)πœ‚π‘›πœ‡π‘§= 0

Since 𝛼(π‘ˆ) =π‘ˆ, we have

𝑧𝛽𝑑(𝑦)πœ‚π‘›πœ‡π‘§= 0for all π‘₯,𝑦 ∈ π‘ˆ,𝑛 ∈ 𝑀

Substitute 𝑧=𝑧𝛽𝑑(𝑦) in above equation and since 𝑀 is semiprime

𝑧𝛽𝑑(𝑦) = 0for all 𝑦,𝑧 ∈ π‘ˆ

Since 𝛼(π‘ˆ) =π‘ˆ, (12)

𝛼(𝑧) 𝛽𝑑(𝑦) = 0

Combining (10) and (12) we get

𝑑(𝑦𝛽𝑧) = 0 for all 𝑦,𝑧 ∈ π‘ˆ

Replace 𝑦 by π‘§π›Ύπ‘š

𝑑(π‘§π›Ύπ‘šπ›½π‘§) = 0 for all π‘š ∈ 𝑀 and 𝛾,𝛽 ∈ Ξ“,𝑧 ∈ π‘ˆ

By the hypothesis and by (12)

𝑑(𝑧)π›Ύπ‘šπ›½π‘‘(𝑧) = 0 β‡’ 𝑑(𝑧)Γ𝑀Γ𝑑(𝑧) = 0 Hence

𝑑(𝑧) = {0}for all 𝑧 ∈ π‘ˆ (13)(ii)

Now assume that 𝑑 acts as an anti- homomorphism on π‘ˆ. By the Lemma 3.6, we have

π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦) = 𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦) (14)

𝑑(𝑦)𝛾𝑦𝛾π‘₯= 𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦) (15)

Replace π‘₯ by π‘₯𝛾𝑑(𝑦) in (14), we get

π‘₯𝛾𝑑(𝑦)𝛾𝛼(𝑦)𝛾𝑑(𝑦) =𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦)𝛾𝑦+𝑑(𝑦)𝛾π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦))by the Lemma3.3

Since 𝛼(π‘ˆ) =π‘ˆ, we have

(5)

Substitute π‘₯𝛾𝑦 for π‘₯ equation (14)

π‘₯𝛾𝑦𝛾𝛼(𝑦)𝛾𝑑(𝑦) = 𝑑(𝑦)𝛾π‘₯𝛾𝑦𝛾𝑑(𝑦) (17)

multiply equation (14) by 𝛼(𝑦)

π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦) = 𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦)𝛾𝛼(𝑦) (18)

Replace π‘₯ by𝑦 in equation (14)

𝑦𝛾𝛼(𝑦)𝛾𝑑(𝑦) = 𝑑(𝑦)𝛾𝑦𝛾𝑑(𝑦)

Multiply byπ‘₯ above relation by

π‘₯𝛾𝑦𝛾𝛼(𝑦)𝛾𝑑(𝑦) =π‘₯𝛾𝑑(𝑦)𝛾𝑦𝛾𝑑(𝑦) (19)

Using (17) (18) and (19) in (16)

π‘₯𝛾𝑦𝛾𝛼(𝑦)𝛾𝑑(𝑦) = π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦) +π‘₯𝛾𝑦𝛾𝛼(𝑦)𝛾𝑑(𝑦)

π‘₯𝛾𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦) = 0

In particular,

π‘₯𝑛𝛾𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦) = 0 where 𝑛 ∈ 𝑀

Hence 𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦)𝛾𝑀𝛾𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦) = {0}

By the semiprimeness of

𝛼(𝑦)𝛾𝑑(𝑦)𝛾𝛼(𝑦) = 0for all π‘₯,𝑦 ∈ π‘ˆ (20)

According to (18) we get

𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦)𝛾𝛼(𝑦) = 0for all π‘₯,𝑦 ∈ π‘ˆ (21)

Replacing π‘₯ by 𝛼(𝑦)𝛾π‘₯𝛾𝑛

𝑑(𝑦)𝛾𝛼(𝑦)𝛾π‘₯𝛾𝑛𝛾𝑑(𝑦)𝛾𝛼(𝑦)𝛾π‘₯= 0

β‡’ 𝑑(𝑦)𝛾𝛼(𝑦)𝛾π‘₯= 0for all π‘₯,𝑦 ∈ π‘ˆ,𝑛 ∈ 𝑀

Since 𝛼(π‘ˆ) =π‘ˆ, we get

𝑑(𝑦)𝛾𝑦𝛾π‘₯= 0 for all π‘₯,𝑦 ∈ π‘ˆ (22)

Using (22) in (15) we obtain

𝑑(𝑦)𝛾π‘₯𝛾𝑑(𝑦) = 0for all π‘₯,𝑦 ∈ π‘ˆ

And so we have

𝑑(𝑦)𝛾π‘₯𝛾𝑛𝛾𝑑(𝑦)𝛾π‘₯= 0for all π‘₯,𝑦 ∈ π‘ˆ,𝑛 ∈ 𝑀

Hence𝑑(𝑦)𝛾π‘₯= 0 for all π‘₯,𝑦 ∈ π‘ˆ (23)

Therefore

π‘₯𝛾𝑑(𝑧)𝛾𝑑(𝑦𝛾𝑛)𝛾π‘₯= 0for all π‘₯,𝑦,𝑧 ∈ π‘ˆπ‘› ∈ 𝑀

By the hypothesis and using Lemma 3.3

π‘₯𝛾𝑑(𝑧)𝛾𝑑(𝑦)𝛾𝑛𝛾π‘₯+ 0 = 0

Since 𝛼(π‘ˆ) =π‘ˆ the second summand is zero by (13)

Hence π‘₯𝛾𝑑(𝑧)𝛾𝑑(𝑦)𝛾𝑀𝛾π‘₯= 0

By the semiprimeness of 𝑀 we get 0 =π‘₯𝛾𝑑(𝑧)𝛾𝑑(𝑦)

=π‘₯𝛾𝑑(𝑧)𝛾𝑦+π‘₯𝛾𝛼(𝑧)𝛾𝑑(𝑦) = π‘₯𝛾𝛼(𝑧)𝛾𝑑(𝑦) = 0

By the semiprimeness of 𝑀,

𝛼(𝑧)𝛾𝑑(𝑦) = 0 for all 𝑧,𝑦 ∈ π‘ˆ (24)

Combining (23) and (24) we have

(6)

Replace 𝑦 by π‘₯𝛾𝑛. By hypothesis and Lemma 3.3 0 =𝑑(π‘₯)𝛾𝑛𝛾𝑑(π‘₯) +𝛼(π‘₯)𝛾𝑑(𝑛)𝛾𝑑(π‘₯)

Since the second summand is zero we get

𝑑(π‘₯)𝛾𝑛𝛾𝑑(π‘₯) = 0

Therefore 𝑑(π‘₯) = 0 for all π‘₯ ∈ π‘ˆ. i.e.,𝑑(π‘ˆ) = 0

Corollary 3.8: Let 𝑀 be a semi prime Ξ“ βˆ’near ring and 𝑑 a (1,𝛼)βˆ’ derivation of 𝑀 Such that 𝛼 is onto and

𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦) for all π‘₯,𝑦 ∈ 𝑀

(i) If 𝑑acts as a homomorphism on 𝑀, then 𝑑= 0

(ii) If 𝑑acts as a anti- homomorphism on 𝑀 such that 𝛼(0) = 0 then 𝑑= 0

Proof: Take π‘ˆ=𝑀 in above theorem we get (i) 𝑑(𝑀) = 0β‡’ 𝑑= 0

(ii) 𝛼(0) = 0then𝑑(𝑀) = 0β‡’ 𝑑= 0

Corollary 3.9: Let 𝑀 be a primeΞ“ βˆ’ near ringand π‘ˆ a non zero subset of 𝑀 such that 0∈ π‘ˆ and π‘ˆΞ“π‘€ βŠ† π‘ˆ. Let 𝑑 be a (1,𝛼)βˆ’ derivation of 𝑀 Such that 𝛼(π‘ˆ) =π‘ˆ and 𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦) for all π‘₯,𝑦 ∈ π‘ˆ

(i) If 𝑑acts as a homomorphism on π‘ˆ, then 𝑑= 0

(ii) If 𝑑acts as an anti- homomorphism on π‘ˆ and 𝛼(0) = 0 then 𝑑= 0

Proof: By the theorem 3.7, we have𝑑(π‘₯) = 0 for all π‘₯ ∈ π‘ˆThen 𝑑(π‘₯𝛾𝑛) =𝑑(π‘₯)𝛾𝑛+𝛼(π‘₯)𝛾𝑑(𝑛) = 𝛼(π‘₯)𝛾𝑑(𝑛) = 0forallπ‘₯ ∈ π‘ˆ,𝑛 ∈ 𝑀. Replace π‘₯ by π‘₯π›Ύπ‘š,𝛼(π‘₯π›Ύπ‘š)𝛾𝑑(𝑛) = 𝛼(π‘₯)𝛾𝛼(π‘š)𝛾𝑑(𝑛) = 0for all π‘₯ ∈ π‘ˆ, 𝑛,π‘š ∈ 𝑀and

𝛾 ∈ Ξ“. Hence π‘₯Ξ“M Γ𝑑(𝑛) = 0. By the primeness of 𝑀 we have π‘₯= 0 or 𝑑(𝑛) = 0 for all π‘₯ ∈ π‘ˆ . Sinceπ‘ˆ is non zero

we have𝑑(𝑛) = 0 for all 𝑛 ∈ 𝑀.

Theorem 3.10: Let 𝑀 be a prime Ξ“ βˆ’near ring π‘ˆ a non zero semigroup ideal of 𝑀 and 𝑑 a non zero(1,𝛼)- derivation of 𝑀 such that 𝛼(π‘₯𝛾𝑦) =𝛼(π‘₯)𝛾𝛼(𝑦) for all π‘₯,𝑦 ∈ π‘ˆ and𝛼(π‘ˆ) =π‘ˆ. If 𝑑(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦) = 0 for all π‘₯,𝑦 ∈ π‘ˆ then (𝑀, +) is abelian.

Proof: Suppose that 𝑑(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦) = 0 for all π‘₯,𝑦 ∈ π‘ˆ.By the Lemma 3.5, we have𝛼(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦)𝛾𝑑(𝑧) = 0 for all π‘₯,𝑦 ∈ π‘ˆ, 𝑧 ∈ 𝑀and 𝛾 ∈ Ξ“..Since 𝑑 β‰ 0 it follows that 𝛼(π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦) = π‘₯+𝑦 βˆ’ π‘₯ βˆ’ 𝑦= 0 for all π‘₯,𝑦 ∈

π‘ˆ. Hence(𝑀, +) is abelian by Lsemma 3.1.

REFERENCE

1. N. Argac, on prime and semiprime near rings with derivations, Internat.J.Math.andMath.Sci.20 (1997), no. 4,

737-740 .

2. N. Argac., On near rings with two-sided 𝛼 βˆ’derivations, Turkish J. Math. 28 (2004), 195-204.

3. H.EBelland G.Mason, On derivations in near-rings, Near-rings and Near-fields [Tiibingen, 1985] of North- Holland Mathematics Studies, North-Holland, Amsterdam, The Netherlands 137(1987), 31-35.

4. L. Madhuchelvi. On Generalized Derivation in Ξ“ βˆ’ Near Rings, Int. Jr, of Mathematical sciences and Applications, vol. 6, No.1, ISSN NO: 2230-9888, Jan-Jun 2016.

5. MustafaKazaz and Akin Alkan, Two-sided Ξ“ βˆ’ 𝛼 βˆ’ derivations in prime and semiprimeΞ“ βˆ’ near rings Commum. Korean Math. Soc. 23 (2008), No.4, pp. 466-477

6. N.Nobusawa, On a generalization of the ring theory, Osaka Journal Math.1 (1964), 81-89.

7. B.Satyanarayana, Contributions to Near ring theory, Doctoral Thesis, Nagarjuna University, India, 1984.

References

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