Introduction:
Preparing for the Mathematics optional subject for the UPSC exam requires extensive practice and familiarity with different types of mathematical problems. Online question banks or practice sets can be a valuable resource in this regard. Here are some effective ways to utilize these resources to enhance your preparation:

1. Choose a reliable online platform:
Select a reputable online platform such as EduRev that provides a wide range of question banks and practice sets specifically designed for the Mathematics optional subject. Make sure the platform offers a diverse set of problems covering different topics and difficulty levels.

2. Understand the syllabus:
Before starting your practice, thoroughly understand the syllabus of the Mathematics optional subject. Divide the syllabus into different topics and subtopics to have a clear idea of what to expect. This will help you navigate through the question banks more efficiently.

3. Systematic approach:
Follow a systematic approach while solving the questions. Start with easier problems and gradually move towards more complex ones. This will help build your confidence and gradually improve your problem-solving skills. Ensure that you cover all the topics in a balanced manner.

4. Time management:
During your practice sessions, allocate a specific amount of time for each question or set of questions. This will help you improve your speed and accuracy, which are crucial for the UPSC exam. As you progress, try to solve questions within the allotted time frame to simulate exam conditions.

5. Analyze your performance:
Regularly assess your performance by analyzing your answers. Identify the areas where you are facing difficulties and focus on improving those particular topics. Keep track of your progress and ensure that you are gradually becoming more comfortable with different types of mathematical problems.

6. Seek explanations and solutions:
While practicing online, make sure the platform provides detailed explanations and solutions for each question. This will help you understand the concepts and techniques required to solve the problems. If you encounter any doubts or difficulties, seek clarification from trusted sources such as textbooks or online forums.

7. Revision and repetition:
Revisit the questions that you have previously attempted to reinforce your understanding. Repetition is key to retaining the concepts and techniques required for solving mathematical problems. Additionally, revise the important formulas, theorems, and concepts regularly to ensure a strong grasp of the subject.

Conclusion:
Using online question banks and practice sets is an effective way to familiarize yourself with different types of mathematical problems for the Mathematics optional subject. By following a systematic approach, managing your time effectively, and analyzing your performance, you can enhance your problem-solving skills and increase your chances of success in the UPSC exam. Remember to practice regularly and seek clarification whenever needed to strengthen your understanding of the subject.