iosr-Jm   Volume-19 ~ Issue-3 ~ May – June 2023

Abstract : Mathematics is a discipline that closely relates to everyday life, making it essential to align its learning with the reality of students. An approach used to bridge the gap between classroom learning and real-life experiences is Realistic Mathematics Learning (RML). By placing the experiences and reality of students at the forefront, RML allows students to learn this subject through activities that develop mathematical tools to solve problems associated with everyday life. The mathematization process, which starts from the real world and progresses to the symbol world, comprises two stages, namely horizontal and vertical. In the horizontal stage, students use their informal experiences........

Keywords: Horizontal Mathematization, Vertical Mathematization, Realistic Mathematics Learning.

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Abstract :The concept in which division by zero results in a defined and logically consistent answer as opposed to the currently accepted "undefined" answer sprung forth from a theory that was developed by applying division to infinitesimal numbers in the hyperreal number line, leading to the discovery of sub-infinitesimals, which are an extension of the concept of the number zero, with the latter assuming the role of the data of numbers. Sub-infinitesimals themselves have no magnitude as they are simply zero, however they serve as a system of identification for numbers describing how in certain situations a number will "react" to certain operations. When considering division by three, which results in a never-ending quotient, speculation that division by 3 was an "imperfect" operation that cannot......

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Abstract : The notion introduced in [1] for 𝑆𝜉− Strictly singular operator in Banach spaces. We extend this notion for super strict singular operator in Locally convex spaces (Lcs). Some properties and characterization for these operators are derived in hereditarily indecomposable(HI) complex Banach spaces.

Keywords: Strictly singular operator, Super strictly singular operator, Hereditarily indecomposable(HI).

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