The Study of Grade 8 Students’ Algebraic Thinking in Solving Problems of Factoring One Variable Polnomials of Degree 2

Abstract

This thesis used mixed research methodsaim to study of algebraric thinking in solving factorization problem of Polynomial Degree 2 One Variable of grade 8 students. The  target group was thirty grade 8 students who were studying in the second semester of academic year 2014, DemonstrationSchool of Khon Kaen University Secondary School. Data collection tools included tests of algebraic thinking on the factorization of polynomial in one variable, which is divided into 3 topics, as follows; 1) the factorization of a polynomial of degree two variables ax² + bx + c on a, b is an integer and c = 0 2) factoring polynomials of degree two variables ax² + bx + c = 1, b, and c is the integer a and b ≠ 0, c ≠ 0 and 3) factoring of polynomial in one variable ax + bx + c, when a, b, c as integer, and a ≠ 0, b ≠ 0, c ≠ 0. The data were analyzed according to the algebraic concept of Pierce and Stacey (2007).

The research results found:

Showed that the algebraic thinking of the students is characterized as follows; 1) recognizing the fundamental elements and properties: the students know the value of each term with integer coefficients. 2) the identity of the structure: students can see the sub structure with common factor. 3) identification of properties that matter: students can pull the joint assembly using the distribution property. In addition, it was founded that most of the students who made errors on factorization because of the lack of algebraic thinking skill.