No, the board examination is not just based on previous years' questions and sample papers. Although these are great sources for knowing the exam's pattern and question type, but these should not be the basis of preparing yourself.

Here's why:

Syllabus and Pattern Changes Boards mostly make minor changes in their syllabus or exam pattern. So, it is not possible to cover up all the topics from previous years' papers.
Conceptual Understanding: Concepts need to be held in mind strongly. Rote learning of previous year's questions may not suffice.
Application of Knowledge: In board examinations, your ability to apply concepts to new situations is tested.

NCERT Textbooks: these should be thoroughly read.
Reference Books: one should try to refer to reference books for extensive practice and explanation.
Previous Year's Papers: analyze these papers to know the exam pattern, question types, and their difficulties
Sample Papers: provide ample practice with sample paper against time
Mock Tests: give simulated experience as in the actual term to test oneself. https://school.careers360.com/boards/cbse

https://school.careers360.com/exams/cbse-class-10th

Hello

Previous Year Question or sample papers are valuable tools for exam preparation . They help students understand the exam pattern , improve time management and identify important topics . By practicing these papers,  students can boost their confidence , assess their strengths and weaknesses and focus their study on areas that need improvement .

Exams generally do not ask the same exact questions as those found in previous years . many questions follow similar patterns or concepts and previous year's questions  often repeat the types of topics or problem solving methods .

The questions might be reworded or slightly changed but the core concepts remain consistent ,  PYQs an excellent resource for exam preparation .

Hope its help .

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