Analisis Miskonsepsi Nilai π pada Materi Lingkaran dalam Buku Senang Belajar Matematika: Antara Nilai Sebenarnya dan Realitas Irasional

Abstract

Understanding mathematical concepts is inseparable from the clarity of their definitions and presentation in textbooks. One fundamental concept that frequently appears in school curricula, from elementary, middle, and high school levels, is the constant π (phi) in the topic of circles. Mathematically, π is an irrational number obtained from the ratio of a circle's circumference to its diameter. However, in practical learning, the value of π is often simplified to  or 3.14. This practical presentation has the potential to lead to misconceptions in students, namely, that they assume π is a rational number. This study used qualitative methods with document analysis techniques in the "Happy Learning Mathematics" book. The results of the analysis indicate an emphasis on the use of the value π =  or 3.14 without explaining its irrational nature. As a result, students tend to memorize practical formulas and numbers without understanding that these two values are only approximations and that π is an irrational number with infinite decimal places.