For a given rational number r, a classical theorem of Niven asserts that if cos(rp) is rational, then cos(rp) [element-of] {0,±1,±1/2}. In this note, we extend Niven's theorem to quadratic irrationalities and present an elementary proof of that.

This literature review covers 42 years and has two main objectives: to identify the obstacles to learning the polar coordinate system and to explore the teaching proposals suggested to overcome them. These questions are answered by locating and analysing articles related to the topic published in research and practitioner journals specialising in…

Problem-based learning (PBL) has the potential to enhance both cognitive and affective engagement but has been criticised for being unsuitable for learners with low levels of knowledge and skills, such as South African learners from poor backgrounds. In such cases, guided problem-based learning (GPBL), which includes direct instruction and teacher…

Helping students to stay motivated by creating an environment that makes them interact is essential to attaining academic achievement. This action research utilizing mixed methods approach explores the flipped classroom's impact on the students' achievement motivation. Also, a significant focus has been on how students interacted with their…