There are specific topics within the Mathematics and General Ability Test (GAT) papers of the NDA (National Defence Academy) exam that have a higher weightage of marks. These topics are important to focus on as they carry more significance in the overall scoring of the exam. Let's break down the key topics for each paper:

Mathematics Paper:
1. Algebra: This topic includes various subtopics such as quadratic equations, polynomials, progressions, matrices, determinants, and logarithms. It holds a significant weightage in the Mathematics paper due to its wide application in solving problems.

2. Trigonometry: Trigonometry is another important topic that carries a higher weightage. It includes concepts related to ratios, identities, heights and distances, and the properties of triangles. Strong knowledge of trigonometry is necessary to solve complex problems involving angles and distances.

3. Calculus: Calculus involves the study of limits, derivatives, and integrals. It is a fundamental branch of mathematics and is given considerable weightage in the NDA Mathematics paper. Understanding the concepts of calculus is crucial as it provides a foundation for solving problems related to rates of change and optimization.

4. Analytical Geometry: This topic encompasses the study of lines, circles, conics, and other geometric figures using algebraic methods. It is an important topic with a higher weightage as it requires a combination of algebraic and geometric skills to solve problems.

General Ability Test (GAT) Paper:
1. English: The English section of the GAT paper includes questions related to grammar, vocabulary, comprehension, and basic language skills. It is an important topic and carries a considerable weightage as it evaluates the candidate's proficiency in the English language.

2. Physics: The Physics section of the GAT paper focuses on topics such as mechanics, optics, thermodynamics, electricity, and magnetism. These topics are given higher weightage as they test the candidate's understanding of fundamental concepts and their application in solving physics-related problems.

3. Chemistry: The Chemistry section covers topics such as atomic structure, periodic table, chemical reactions, acids and bases, and organic chemistry. It carries a significant weightage in the GAT paper as it assesses the candidate's knowledge of basic chemical principles and their ability to apply them in problem-solving.

4. General Knowledge: The General Knowledge section is vast and covers a wide range of topics including current affairs, history, geography, politics, economics, and sports. It is an important section with higher weightage as it evaluates the candidate's awareness, knowledge, and understanding of the world around them.

In conclusion, while all topics within the Mathematics and GAT papers are important for the NDA exam, certain topics carry a higher weightage of marks. It is crucial for candidates to focus on these specific topics and allocate their study time accordingly to maximize their chances of success in the exam.