Education is one of the determinants of the advancement or decline of a nation's civilization. Therefore, in this modern era, education plays a crucial role in creating generations capable of keeping up with the rapid development of knowledge, including the field of mathematics (Susilawati, 2020). Mathematics is one of the subjects studied at every level of education, from elementary school, middle school, and high school to university. Mathematics also plays an essential role in various other disciplines and serves the function of developing human intellect. Therefore, students must master mathematics as it will enhance their understanding in other fields. Mathematics can be used as a tool, a science, a guiding framework, and also as a form of attitude (E, 2010). Currently, the world has entered the 21st century, also known as the global era, which demands mastery of specific skills. To compete in the global era, students need to become proficient communicators, creators, critical thinkers, and collaborators beyond basic reading, writing, and arithmetic skills (Wulandari & Azka, 2018).

The process of mathematics learning is not merely the transfer of knowledge from the teacher to the students, but rather a process conditioned or facilitated by the teacher, so that students actively construct or build their knowledge in various ways. It involves interactions and negotiations between the teacher and students, as well as among students themselves. The intended mathematics education is meaningful, so that students gain something beneficial for themselves after completing the learning process (Sholihah et al., 2018). The National Council of Teachers of Mathematics (N.C.T.M., 2000) formulates the objectives of mathematics learning as follows: 1) learning to communicate mathematically (mathematical communication), learning to reason mathematically (mathematical reasoning), learning to solve problems (problem-solving), and learning to connect ideas (mathematical representation). Based on the objectives of mathematics learning, it can be concluded that mathematics education can help students understand concepts, solve problems systematically, relate mathematics to everyday life, and express mathematical ideas effectively both orally and in writing. One of the mathematical abilities that students should possess is mathematical communication skills (Anwar, 2018).

Mathematical communication skills are crucial during student discussions, where students are expected to express, explain, describe, listen, inquire, and collaborate to deeply understand mathematics. In short, communication is seen as a way to convey ideas, thoughts, and feelings to others (Ahdhianto et al., 2020). Furthermore, research conducted by (Wardhana & Lutfianto, 2018), states that students' mathematical communication skills still yield unsatisfactory results. This is further supported by a research conducted by (Prentha, 2021) which mentions that in a discussion with students, the communication is not well-executed, both orally and in writing. Students face difficulties in presenting arguments, even though they have mathematical ideas and concepts in their minds.

In addition to mathematical communication skills, problem-solving abilities are also crucial to be developed in the process of learning mathematics. Problem-solving skills need to be enhanced in mathematics education to improve students' thinking patterns. Students think that by knowing the formula, they can solve problems. However, in reality, it is often found that only a few students who use the 'formula' can successfully find the correct solution. This indicates that students sometimes are unable to solve problems even if they know the formula (Toksoy & Akdeniz, 2015). If students frequently practice solving mathematical problems and contextual questions, then the mathematical problem-solving skills within the students and the mathematics learning activities become a pattern of good problem-solving habits, leading to the achievement of learning objectives.

In addition to the cognitive domain, students' psychological attitudes in learning also need to be taken into consideration, given that the goal of education in schools is not only to transfer knowledge but also to shape students' behavior and attitudes towards mathematics and its application in daily life. Regarding students' psychological attitudes, there is a psychological aspect closely related to students' problem-solving activities, which is self-efficacy. Self-efficacy is the belief of students regarding their ability to accomplish a task or solve a problem (Akça & Alabay, 2023). Besides the influence of individual differences on students' motivation and achievement, self-efficacy is one aspect that can determine whether students succeed or fail in mathematics learning. Self-efficacy is known to affect students' academic motivation, effort, perseverance, and emotional reactions (Shi & Ko, 2023). Having high self-efficacy can encourage someone to continuously attempt to learn and perform tasks, leading to successful task completion (Djatmika et al., 2022).

The research conducted by Bong (Kamalimoghaddam et al., 2016), (Kamalimoghaddam et al., 2016) also found that the higher the students' self-efficacy, the higher their learning effort. Therefore, students' belief in their own abilities to solve mathematical problems is crucial because without self-confidence, students cannot complete a task optimally. Student-centered learning initiates the learning process with contextual problems. This is because if students can optimize their problem-solving abilities through contextual problems, their learning achievement will also improve. As emphasized by (Ninnuan & Wongsaphan, 2022) appropriate learning can enhance the quality of students' mathematical problem-solving skills, leading to improved learning achievement.

One of the learning models that can enhance mathematical communication and problem-solving skills is discovery learning. Discovery learning is a learning model that focuses on providing direct opportunities for active learning for students (Usman et al., 2022). According to Bicnell, there are three main attributes of discovery learning, such as: 1) investigating and solving problems to create, integrate, and equalize knowledge, 2) Encouraging students to learn based on their own ways/steps, where students determine the frequency and sequence. 3) Activities to promote the integration of existing knowledge principles as a basis for building new knowledge. In other words, this guided discovery model exposes students to situations where they are free to investigate and draw conclusions, make guesses, use intuition, and engage in trial and error.

The scientific approach is a learning approach designed in such a way that students actively construct concepts, knowledge, laws, or principles through a scientific method (Mahmudi, 2015). The scientific approach means a learning model that focuses on developing students' problem-solving skills and critical thinking in real-life contexts related to the learning concepts (Maharani et al., 2020). In addition to the scientific approach, the cooperative model is also one of the learning models in which students learn in small groups with different levels of ability. The group learning process encourages students to help each other, fostering a sense of togetherness and unity in achieving common goals (Haenilah et al., 2021).

Based on the description above, this research applies a mathematics teaching strategy using the scientific approach with the discovery learning model for 10th-grade students in high school on the topic of KD 3.8. Generalizing trigonometric ratios for angles in various quadrants and related angles, and KD 4.8. Solving contextual problems related to trigonometric ratios of angles in various quadrants and related angles to support the improvement of communication, problem-solving, and self-efficacy skills.

This research is a quantitative research, and the type of research applied in this research is quasi-experiment (Creswell, 2014). The research design used is a one-group pretest-posttest design, aimed at determining the students' competence in mathematics learning on the topic of trigonometric ratios. A one-group pretest-posttest design is used to evaluate the effectiveness of implementing a program (Ma et al., 2019); (Gao et al., 2016). The implementation of this research was carried out by (Koller & Stuart, 2016) in evaluating the influence of stigma on schools in Canada. Before the implementation of the learning process, the students were first given a pretest to assess their initial competence. After the learning process, the students were given a posttest to assess their competence after the implementation of the learning process using the scientific approach with the discovery learning model, which supports communication, problem-solving, and self-efficacy skills. This research was conducted in 10th-grade at one of the public high schools in West Aceh, with a population of 29 students. Based on the presented research design, as shown in Table 1.

The data collection technique in this research employs both test and non-test methods. The problem-solving and communication abilities of students are measured using test instruments, while the self-efficacy of students and the implementation of the applied learning are measured using non-test instruments.

The data obtained in this research are the results of pretests and posttests conducted in grade X at SMAN 4 Wira Bangsa Aceh Barat with a population of 29 students. To assess the students' competencies, the researcher administered a pretest before the instruction and a posttest after the instruction to the participants. This pretest is an assessment of learning outcomes and abilities in communication, problem-solving, and self-efficacy, administered before the mathematics learning process on the topic of trigonometric ratios. On the other hand, the posttest is an assessment of learning outcomes and abilities in communication, problem-solving, and self-efficacy given after the mathematics learning process on the topic of trigonometric ratios. Subsequently, the researcher conducted a trial on the participants. The data obtained were then analyzed. The results of the pretest and posttest are presented in Table 2.

Based on Table 2, the average pretest score is 35.08383 with a standard deviation of 5.1, and the average posttest score is 82.2433 with a standard deviation of 4.7. The maximum score on the pretest is 50, while on the posttest, it is 88. The minimum score on the pretest is 11, whereas on the posttest, it is 60. These results indicate that the implementation of mathematics learning processes on the topic of trigonometric ratios using the discovery learning approach has an impact on students' communication, problem-solving, and self-efficacy abilities in grade X. The purpose of this analysis is to evaluate the characteristics of the data obtained after the pretest and posttest.

Hypothesis testing aims to examine the improvement in communication, problem-solving, and self-efficacy abilities after receiving a treatment, compared to before the treatment. The research hypothesis will be tested using the following criteria. is rejected if ttable (α − 1) < tcount, and is accepted if ttable (α − 1) > tcount, with α = 5%, which means the average statistical literacy score of students is at least or greater than the Minimum Competency Criteria (MCC) of 70. Next, further testing was carried out to determine significant differences between the pretest and posttest results using the t-test assisted by the SPSS application. Data including normality tests for pretest and posttest scores on communication skills, problem solving and self-efficacy were analyzed using the Shapiro-Wilk test. The following table shows the results of the Paired Sample T-Test carried out in Table 3.

Based on the results of the analysis in Table 3 above, the results show that the pretest and posttest scores for communication skills, problem solving and self-efficacy are normally distributed. Next, test will be carried out for each ability which will be presented in the table below. In Table 4,

the significance score of the t-test calculation using SPSS on mathematical communication skills is 0.000 < 0.05. Therefore, it can be concluded that there is a significant difference between the pretest and posttest scores of the mathematical communication taught. using a scientific approach through the Discovery Learning model.

In Table 5, the results of the t-test calculation using SPSS show that the significance score for problem solving is 0.000 < 0.05. Therefore, it can be concluded that there is a significant difference between the pretest and posttest scores for problem solving taught using a scientific approach

through the Discovery learning model. In Table 6, the significance score obtained from the t test calculation using SPSS is 0.000 < 0.05. Therefore, it can be concluded that there is a significant difference between the pretest and posttest self-efficacy questionnaires taught using a scientific approach through the Discovery Learning model.

Based on the results of the calculation using SPSS, it can be observed that the average increase in N-gain_score is 70.87. Therefore, it can be concluded that there is an improvement in Communication skills through the implementation of the scientific approach using the discovery learning model, categorized as moderately effective, as shown in Table 7. Based on the results of the calculation using SPSS, it can be observed that the average increase in N-gain_score is 71.61. Therefore, it can be concluded that there is an improvement in Problem-Solving skills through the implementation of the scientific approach using the discovery learning model, categorized as moderately effective, as shown in Table 8.

On the subject of trigonometric comparisons, there was an impact of using a scientific method with the discovery learning model on students' mathematical communication abilities, problem solving, and self-efficacy before and after the learning process. It is hoped that more research will be done to identify other competencies that students need to have in other courses, and math teachers should be able to create math learning practices that use cutting-edge teaching strategies to help students become more competent.

The author would like to thank all participants in this study. Their kind and selfless collaboration would like to thank all participants in this research who have collaborated well and selflessly in completing this research.