This study investigates the effectiveness of applied methodologies in the instruction of differential calculus for undergraduate students. By integrating problem-solving techniques and project-based learning, we aim to enhance students' comprehension and application of differential calculus concepts. The study involves a mixed-methods approach, utilizing both quantitative and qualitative data to assess the impact of these methodologies on students' performance and engagement. Results indicate a significant improvement in students' understanding and retention of course material, as well as increased motivation and interest in mathematics.