Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 6s (2025) 290 https://internationalpubls.com Pythagorean Neutrosophic Cubic Set 1Berna Joyce L, 2Dr.Elvina Mary L 1, 2PG and Research Department of Mathematics, Nirmala College for Women, Coimbatore, India. Email Id: bernajoyceslr@gmail.com1, corresponding author: elvinalawrence07@gmail.com Article History: Received: 19-10-2024 Revised: 03-12-2024 Accepted: 11-12-2024 Abstract: The purpose of this work is to broaden the definition of Neutrosophic Cubic Set (NCS) and Pythagorean Cubic Set (PCS) to Pythagorean Neutrosophic Cubic Set (PNCS). Related qualities are examined and the concepts of T-external, I-external, and F-external Pythagorean Neutrosophic Cubic Set (PNCS) and T-internal, I-internal, and F-internal PNCS are conveyed. Keywords: Pythaogrean Neutrosophic Cubic Set Pythagorean Neutrosophic Internal Cubic Set, Pythagorean Neutrosophic External Cubic Set. 1. Introduction Zadeh[8] established a foundation for fuzzy mathematics in 1965. Soon after, in 1975, Zadeh[8] proposed a reconfiguration of fuzzy sets with interval valued function membership. Neutrosophic Sets were initially defined in 1995 by Florentin Smarandache[5]. This enables ambiguity and uncertainty to be handled more thoroughly. In the year 2012, the introduction of the important theory of Cubic Sets was defined by Jun et al[2]. In 2017, Chang Su Kim, Florentin Smarandache, and Young Bae Jun[3] presented the an idea of Neutrosophic Cubic Sets. Yagar[7] first presented the Pythagorean Fuzzy set's evolution in 2013. In 2019, F. Khana, M. S. Ali Khana, M. Shahzada, and S. Abdullah[4] gave a concept of the Pythagorean Cubic Fuzzy Set. R. Jhansi & K. Mohana[1] proposed the Neutrosophic Pythagorean Sets. The interval-valued Neutrosophic Pythagorean Sets were presented by Stephy et al[6]. This article tries to establish an innovative concept known as Pythagorean Neutrosophic Cubic Sets (PNCS) which is a combination of PNS and PNIVS. 2. Preliminaries Definition 2.1[2] If Ξ™Μ‚ β‰  πœ™. Then a cubic set, �̂�𝐢𝑆 = {βŒ©π‘–Μ‚, �̂�𝐹𝐼𝑆(𝑖̂), �̂�𝐹𝑆(𝑖̂)βŒͺ: 𝑖̂ ∈ Ξ™Μ‚} where �̂�𝐹𝐼𝑆(𝑖̂) is IVFS, �̂�𝐹𝑆(𝑖̂) is a fuzzy set. Definition 2.2[2] Let Ξ™Μ‚ β‰  πœ™. A cubic set �̂�𝐢𝑆 = βŒ©οΏ½Μ‚οΏ½πΉπΌπ‘†(𝑖̂), �̂�𝐹𝑆(𝑖̂)βŒͺ in Ξ™Μ‚ is called an ICS if �̂�𝐹𝐼𝑆 βˆ’ (𝑖̂) ≀ �̂�𝐹𝑆(𝑖̂) ≀ �̂�𝐹𝐼𝑆 + (𝑖̂) for all 𝑖̂ ∈ Ξ™Μ‚. Definition 2.3 [2] If Ξ™Μ‚ β‰  πœ™ set. A cubic set �̂�𝐢𝑆 = βŒ©οΏ½Μ‚οΏ½πΉπΌπ‘†(𝑖̂), ℓ̂𝐹𝑆(𝑖̂)βŒͺ in X is called an ECS if �̂�𝐹𝑆(𝑖̂) βˆ‰ (�̂�𝐹𝐼𝑆 βˆ’ (𝑖̂), �̂�𝐹𝐼𝑆 + (𝑖̂)) . Definition 2.4[1] Let Ξ™Μ‚ β‰  πœ™. A PNS in Ξ™Μ‚ 𝑖𝑠 �̂�𝑃𝑁𝑆 = {βŒ©π‘–Μ‚, 𝒯�̂�(𝑖̂), ℐ�̂�(𝑖)Μ‚, β„±οΏ½Μ‚οΏ½(𝑖̂)βŒͺ: 𝑖̂ ∈ Ξ™Μ‚} where 𝒯𝐴(𝑖)Μ‚, ℐ�̂�(𝑖̂), β„±οΏ½Μ‚οΏ½(𝑖̂): Ξ™Μ‚ β†’ [0,1] & 0 ≀ (𝒯�̂�(𝑖̂)) 2 + (ℐ�̂�(𝑖̂)) 2 + (β„±οΏ½Μ‚οΏ½(𝑖̂)) 2 ≀ 2 where 𝒯�̂�(𝑖̂) denotes the degree of membership, , ℐ�̂�(𝑖̂) denotes the degree of indeterminacy and β„±οΏ½Μ‚οΏ½(𝑖)Μ‚ denotes the degree of non-membership. Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 6s (2025) 291 https://internationalpubls.com Definition 2.5[6] Let Ξ™Μ‚ β‰  πœ™, PNIVS is of the form, �̂�𝑃𝑁𝐼𝑉𝑆{βŒ©π‘–Μ‚, 𝒯�̂�(𝑖̂𝑃𝑁𝐼𝑉𝑆), ℐ�̂�(𝑖̂𝑃𝑁𝐼𝑉𝑆), β„±οΏ½Μ‚οΏ½(𝑖̂𝑃𝑁𝐼𝑉𝑆)βŒͺ: 𝑖̂𝑃𝑁𝐼𝑉𝑆Ι̂} where𝒯�̂�(𝑖̂𝑃𝑁𝐼𝑉𝑆)[𝒯�̂� βˆ’(𝑖̂𝑃𝑁𝐼𝑉𝑆), 𝒯�̂� +(𝑖̂𝑃𝑁𝐼𝑉𝑆)], ℐ�̂�(𝑖̂𝑃𝑁𝐼𝑉𝑆) = [ℐ�̂� βˆ’(𝑖̂𝑃𝑁𝐼𝑉𝑆), ℐ�̂� +(𝑖̂𝑃𝑁𝐼𝑉𝑆)] and β„±οΏ½Μ‚οΏ½(𝑖̂𝑃𝑁𝐼𝑉𝑆) = [β„±οΏ½Μ‚οΏ½ βˆ’(𝑖̂𝑃𝑁𝐼𝑉𝑆), β„±οΏ½Μ‚οΏ½ +(𝑖�̂�𝑁𝐼𝑉𝑆)]. Consider the mapping 𝒯�̂�(𝑖̂𝑃𝑁𝐼𝑉𝑆), ℐ�̂�(𝑖̂𝑃𝑁𝐼𝑉𝑆), β„±οΏ½Μ‚οΏ½(𝑖̂𝑃𝑁𝐼𝑉𝑆): Ξ™Μ‚ β†’ [0,1] and 0 ≀ [ 𝒯 οΏ½Μ‚οΏ½ βˆ’(�̂�𝑃𝑁𝐼𝑉𝑆)+𝒯 οΏ½Μ‚οΏ½ +(�̂�𝑃𝑁𝐼𝑉𝑆) 2 ] 2 + [ ℐ οΏ½Μ‚οΏ½ βˆ’(�̂�𝑃𝑁𝐼𝑉𝑆)+ℐ οΏ½Μ‚οΏ½ +(�̂�𝑃𝑁𝐼𝑉𝑆) 2 ] 2 + [ β„± οΏ½Μ‚οΏ½ βˆ’(�̂�𝑃𝑁𝐼𝑉𝑆)+β„± οΏ½Μ‚οΏ½ +(�̂�𝑃𝑁𝐼𝑉𝑆) 2 ] 2 ≀ 2 3. Pythagorean Neutrosophic Cubic Set (PNCS) Definition 3.1 Let οΏ½Μ‚οΏ½ β‰  πœ™, a Pythagorean Neutrosophic Cubic Set (PNCS), having a form, �̂�𝑃𝑁𝐢𝑆 = {βŒ©πœ„,Μ‚ �̂�𝑃𝑁𝐼𝑉𝑆(πœ„ Μ‚Μ‚), πœ›π‘ƒπ‘π‘†(πœ„)Μ‚βŒͺ: πœ„ Μ‚ ∈ Ξ™Μ‚} where �̂�𝑃𝑁𝐼𝑉𝑆(πœ„)Μ‚ represent the Pythagorean Neutrosophic Interval valued set in Ξ™Μ‚. πœ›π‘ƒπ‘π‘†(πœ„)Μ‚ represent the Pythagorean Neutrosophic Set. PNCS can be denoted as a pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›). Example 3.2 If οΏ½Μ‚οΏ½ = {β„Ž, π‘Ÿ, 𝑣} then �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›)with the tabular representation given below, οΏ½Μ‚οΏ½ �̂�𝑃𝑁𝐼𝑉𝑆(πœ„ Μ‚Μ‚) πœ›π‘ƒπ‘π‘†(πœ„)Μ‚ h ([0.2,0.3], [0.3,0.5], [0.4,0.6]) (0.1,0.2,0.3) r ([0.1,0.4], [0.3,0.7], [0.4,0.8]) (0.3,0.2,0.7) v ([0.2,0.3], [0.4,0.8], [0.3,0.5]) (0.5,0.2,0.3) Table 1 – Example of PNCS Therefore, �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) �̂�𝑃𝑁𝐢𝑆 = { βŒ©β„Ž, ([0.2,0.3], [0.3,0.5], [0.4,0.6]), (0.1,0.2,0.3)βŒͺ, βŒ©π‘Ÿ, ([0.1,0.4], [0.3,0.7], [0.4,0.8]), (0.3,0.2,0.7)βŒͺ, βŒ©π‘£, ([0.2,0.3], [0.4,0.8], [0.3,0.5]), (0.5,0.2,0.3)βŒͺ } The pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is called PNCS. Definition 3.3 Let οΏ½Μ‚οΏ½ β‰  πœ™. A PNCS �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) in οΏ½Μ‚οΏ½is said to be οΏ½Μ‚οΏ½-internal, (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) ≀ π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½. 𝐼-internal if (π•€π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•€(�̂�𝑃𝑁𝐢𝑆) ≀ π•€π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½. οΏ½Μ‚οΏ½-internal if (π”½π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π”½(�̂�𝑃𝑁𝐢𝑆) ≀ π”½π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½. If a PNCS �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›)in οΏ½Μ‚οΏ½ adheres to the aforementioned shortcomings then, �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is an IPNCS. Example 3.4 Let Ξ™Μ‚ = {β„Ž, π‘Ÿ, 𝑣}. Then the pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) with the tabular representation given below, οΏ½Μ‚οΏ½ �̂�𝑃𝑁𝐼𝑉𝑆(�̂�𝑃𝑁𝐢𝑆) πœ›π‘ƒπ‘π‘†(�̂�𝑃𝑁𝐢𝑆) h ([0.1,0.3], [0.4,0.6], [0.5,0.8]) (0.25,0.48,0.62) r ([0.1,0.4], [0.3,0.7], [0.4,0.8]) (0.30,0.58,0.71) v ([0.2,0.3], [0.4,0.8], [0.3,0.5]) (0.27,0.65,0.47) Table 2 – Example of IPNCS Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 6s (2025) 292 https://internationalpubls.com Therefore, �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›), �̂�𝑃𝑁𝐢𝑆 = { βŒ©β„Ž, ([0.1,0.3], [0.4,0.6], [0.5,0.8]), (0.25,0.48,0.62)βŒͺ, βŒ©π‘Ÿ, ([0.1,0.4], [0.3,0.7], [0.4,0.8]), (0.30,0.58,0.71)βŒͺ, βŒ©π‘£, ([0.2,0.3], [0.4,0.8], [0.3,0.5]), (0.27,0.65,0.47)βŒͺ } The pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) satisfies, (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) ≀ π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)), (π•€π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•€(�̂�𝑃𝑁𝐢𝑆) ≀ π•€π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)),(π”½π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π”½(�̂�𝑃𝑁𝐢𝑆) ≀ π”½π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)). Then the pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is called IPNCS. Definition 3.5 Let οΏ½Μ‚οΏ½ β‰  πœ™. A PNCS �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) in οΏ½Μ‚οΏ½ is said to be οΏ½Μ‚οΏ½-external, πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½, 𝐼-external if πœ›π•€(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π•€π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π•€π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½ & οΏ½Μ‚οΏ½-external if πœ›π”½(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π”½π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π”½π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½. If a PNCS satisfies the above inequalities then, �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is an EPNCS. Example 3.6 Let Ξ™Μ‚ = {β„Ž, π‘Ÿ, 𝑣}. Then the pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) with the tabular representation given below, οΏ½Μ‚οΏ½ �̂�𝑃𝑁𝐼𝑉𝑆(�̂�𝑃𝑁𝐢𝑆) πœ›π‘ƒπ‘π‘†(�̂�𝑃𝑁𝐢𝑆) h ([0.1,0.3], [0.4,0.6], [0.5,0.8]) (0.4,0.7,0.3) r ([0.1,0.4], [0.3,0.7], [0.4,0.8]) (0.5, 0.2, 0.9) v ([0.2,0.3], [0.6,0.8], [0.3,0.5]) (0.1, 0.5, 0.6) Table 2 – Example of EPNCS Therefore,�̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) �̂�𝑃𝑁𝐢𝑆 = { βŒ©β„Ž, ([0.1,0.3], [0.4,0.6], [0.5,0.8]), (0.4,0.7,0.3)βŒͺ, βŒ©π‘Ÿ, ([0.1,0.4], [0.3,0.7], [0.4,0.8]), (0.5, 0.2, 0.9)βŒͺ, βŒ©π‘£, ([0.2,0.3], [0.6,0.8], [0.3,0.5]), (0.1, 0.5, 0.6)βŒͺ }. Then the pair �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›)is called EPNCS. Theorem 3.7 Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be a PNCS in οΏ½Μ‚οΏ½ β‰  πœ™ which is not EPNCS. Then there exists �̂�𝑃𝑁𝐢𝑆 ∈ Ξ™Μ‚ such that πœ›π‘ƒπ‘π‘†(�̂�𝑃𝑁𝐢𝑆) ∈ �̂�𝑃𝑁𝐼𝑉𝑆(�̂�𝑃𝑁𝐢𝑆). Proof: Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS. Given that �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is not external. Then �̂�𝑃𝑁𝐢𝑆 does not satisfies the following conditions, i.e., πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) , πœ›π•€(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π•€π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π•€π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) , πœ›π”½(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π”½π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π”½π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)) βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½ . Then �̂�𝑃𝑁𝐢𝑆 must be IPNCS.∴ πœ›π‘ƒπ‘π‘†(�̂�𝑃𝑁𝐢𝑆) ∈ �̂�𝑃𝑁𝐼𝑉𝑆(�̂�𝑃𝑁𝐢𝑆). Theorem 3.8 Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 6s (2025) 293 https://internationalpubls.com Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS in οΏ½Μ‚οΏ½ β‰  πœ™ which is not T-IPNCS then exists �̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½, πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) βˆ‰ π•‹π’Ÿ(�̂�𝑃𝑁𝐢𝑆). Proof Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS. Given that �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is not T-IPNCS. Then �̂�𝑃𝑁𝐢𝑆 does not satisfies, (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) ≀ π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)). Therefore,πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) βˆ‰ π•‹π’Ÿ(�̂�𝑃𝑁𝐢𝑆) Theorem 3.10 Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS in οΏ½Μ‚οΏ½ β‰  πœ™ which is not I-IPNCS then exists �̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½, πœ›π•€(�̂�𝑃𝑁𝐢𝑆) βˆ‰ π•€π’Ÿ(�̂�𝑃𝑁𝐢𝑆) Proof Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS. Given that �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is not I-IPNCS. Then �̂�𝑃𝑁𝐢𝑆 does not satisfies, (π•€π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•€(�̂�𝑃𝑁𝐢𝑆) ≀ π•€π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)). Therefore,πœ›π•€(�̂�𝑃𝑁𝐢𝑆) βˆ‰ π•€π’Ÿ(�̂�𝑃𝑁𝐢𝑆) Theorem 3.11 Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS in οΏ½Μ‚οΏ½ β‰  πœ™ which is not F-IPNCS then exists �̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½, πœ›π”½(�̂�𝑃𝑁𝐢𝑆) βˆ‰ π”½π’Ÿ(�̂�𝑃𝑁𝐢𝑆). Proof Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS. Given that �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is not F-IPNCS. Then �̂�𝑃𝑁𝐢𝑆 does not satisfies, (π”½π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π”½(�̂�𝑃𝑁𝐢𝑆) ≀ π”½π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)). Therefore,πœ›π”½(�̂�𝑃𝑁𝐢𝑆) βˆ‰ π”½π’Ÿ(�̂�𝑃𝑁𝐢𝑆). Theorem 3.12 Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS οΏ½Μ‚οΏ½ β‰  πœ™. If �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is both T-IPNCS and T-EPNCS then (βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½) (πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) ∈ {π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½} βˆͺ {π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½}) Proof Let�̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS. If �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is T-IPNCS then βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½, (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) ≀ πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) ≀ π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)). If �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is T-EPNC then βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½ πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) βˆ‰ (π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆), π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆))Then it indicates βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½, πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) = π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆) or πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) = π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆) and so that (πœ›π•‹(�̂�𝑃𝑁𝐢𝑆) ∈ {π•‹π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½} βˆͺ {π•‹π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½}) Theorem 3.13 Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS οΏ½Μ‚οΏ½ β‰  πœ™. If �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is both I-IPNCS and I-EPNCS then (βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½) (πœ›π•€(�̂�𝑃𝑁𝐢𝑆) ∈ {π•€π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½} βˆͺ {π•€π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½}). Communications on Applied Nonlinear Analysis ISSN: 1074-133X Vol 32 No. 6s (2025) 294 https://internationalpubls.com Proof: Forthright. Theorem 3.14 Let �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) be PNCS οΏ½Μ‚οΏ½ β‰  πœ™. If �̂�𝑃𝑁𝐢𝑆 = (οΏ½Μ‚οΏ½, πœ›) is both F-IPNCS and F-EPNCS then (βˆ€οΏ½Μ‚οΏ½π‘ƒπ‘πΆπ‘† ∈ οΏ½Μ‚οΏ½) (πœ›π”½(�̂�𝑃𝑁𝐢𝑆) ∈ {π”½π’Ÿ βˆ’(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½} βˆͺ {π”½π’Ÿ +(�̂�𝑃𝑁𝐢𝑆)|�̂�𝑃𝑁𝐢𝑆 ∈ οΏ½Μ‚οΏ½}). Proof: Forthright. Refrences [1] R. Jhansi, K. Mohana , Florentin Smarandache, Correlation Measure of Pythagorean Neutrosophic sets with T and F as Dependent Neutrosophic Components, Neutrosophic sets and systems, 2021, vol 30,203-212. [2] Jun Y. B., Kim C. S., and Yang K. O., Cubic sets, Annals of Fuzzy Mathematics and Informatics. 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