Journals / Hacettepe Journal of Mathematics and Statistics / 2026 / Volume: 48 Issue: 3

Some characterizations of inner product spaces based on angle

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Publication Date
2019-06-15
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

We also speak about a notion of orthogonality concerning it, we call it $\theta$-orthogonality.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:A problem in functional analysis that arises naturally is about finding necessary and sufficient conditions for a normed space to be an inner product space.
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Key Findings & Data:We introduce a notion of angle between two vectors in a normed space, denoted by $A_\theta(.,.)$ where $\theta\neq{k\pi\over2}$.
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Conclusion & Impact:We also speak about a notion of orthogonality concerning it, we call it $\theta$-orthogonality.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:inner product · normed space · angle

Abstract

A problem in functional analysis that arises naturally is about finding necessary and sufficient conditions for a normed space to be an inner product space. By answering this question, mathematicians try to understand the inner product and normed spaces features. In this note, we have discussed this issue and we prove some results concerned with it. We introduce a notion of angle between two vectors in a normed space, denoted by $A_\theta(.,.)$ where $\theta\neq{k\pi\over2}$. We also speak about a notion of orthogonality concerning it, we call it $\theta$-orthogonality.

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Cite This Article

Sales, S. N. (2019). Some characterizations of inner product spaces based on angle. Hacettepe Journal of Mathematics and Statistics, Volume: 48 Issue: 3. https://doi.org/10.15672/hujms.574044

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