If you fail in two subjects in Physics and Chemistry and want to improve your marks in Mathematics for CBSE Class 12, you have a few options:

1. Appear for Improvement Exams : CBSE allows students to appear for improvement exams for subjects in which they want to improve their marks. You can reappear for Physics and Chemistry to pass those subjects and also appear for the Mathematics improvement exam to enhance your score in that subject.

2. Focus on Mathematics Preparation : Since you want to improve your marks in Mathematics, dedicate more time to studying and practicing Mathematics. Focus on understanding the concepts, solving problems, and practicing previous year question papers.

3. Seek Guidance : Consider seeking guidance from teachers, tutors, or online resources to strengthen your understanding of Physics, Chemistry, and Mathematics topics.

4. Maintain a Balanced Approach : While focusing on Mathematics improvement, don't neglect Physics and Chemistry. Allocate your study time wisely to cover all subjects effectively.

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