PENERAPAN MODEL COOPERATIVE LEARNING TIPE TEAM ASSISTED INDIVIDUALIZATION (TAI) UNTUK MENINGKATKAN KEMAMPUAN PENALARAN DAN KOMUNIKASI MATEMATIS SERTA MENGEMBANGKAN SELF-EFFICACY PESERTA DIDIK SMA: Komunikasi: Penalaran: Self-efficacy: Team Assisted Individualization

Pendekatan penelitian yang digunakan adalah mixed methods  dengan  convergen design. Instrumen yang digunakan berupa soal tes kemampuan penalaran dan komunikasi, angket self efficacy, lembar observasi guru dan peserta didik, juga wawancara. Berdasarkan hasil penelitian yang telah dilaksanakan dari sebanyak Sembilan kali pertemuan menunjukkan bahwa : 1) penerapan model cooperative learning tipe Time Assisted Individualization (TAI) dapat meningkatkan kemampuan penalaran peserta didik; 2) penerapan model cooperative learning tipe Time Assisted Individualization (TAI) dapat meningkatkan kemampuan komunikasi peserta didik; 3) kemampuan penalaran dan komunikasi matematis selama pembelajaran berlangsung dapat diatasi dengan baik, dan ada peningkatan pada setiap pertemuan; 4) perkembangan self-eficacy peserta didik selama proses pembelajaran matematika dengan penerapan model cooperative learning  tipe Time Assisted Individualization (TAI) berada pada kategori sedang, baik secara keseluruhan maupun berdasarkan dimensi magnitude, strength, dan generality; 5) terdapat hubungan yang positif antara kemampuan penalaran dan kemampuan komunikasi matematis dengan self efficacy peserta didik; 6) kendala yang dihadapi peserta didik dalam menyelesaikan tes kemampuan penalaran dan komunikasi matematis bisa diatasi dalam batas pencapaian kriteria ketuntasan minimal yang sudah ditetapkan pada awal penelitian dan didakan evaluasi dalam setiap pertemuannya.The research approach used is mixed methods with convergent design. The instruments used were tests of reasoning and communication skills, self efficacy questionnaires, teacher and student observation sheets, as well as interviews. Based on the results of research that has been carried out from as many as nine meetings showed that: 1) the application of the cooperative learning model Time Assisted Individualization (TAI) type can improve students' reasoning abilities; 2) the application of the cooperative learning model Time Assisted Individualization (TAI) type can improve students' communication skills; 3) mathematical reasoning and communication skills during the learning process can be overcome properly, and there is an increase in each meeting; 4) the development of students' self-efficacy during the mathematics learning process by applying the cooperative learning model Time Assisted Individualization (TAI) type is in the medium category, both overall and based on the dimensions of magnitude, strength, and generality; 5) there is a positive relationship between reasoning abilities and mathematical communication skills with students' self efficacy; 6) the obstacles faced by students in completing mathematical reasoning and communication skills tests can be overcome within the limits of achieving the minimum completeness criteria that have been set at the beginning of the study and are evaluated in each meeting