Q69.Let A be a symmetric matrix of order 2 with integer entries. If the sum of the diagonal elements of A2 is 1, then the possible number of such matrices is: (1) 12 (2) 4 (3) 1 (4) 6
What This Question Tests
This question requires understanding properties of symmetric matrices, performing matrix multiplication, and calculating the sum of diagonal elements (trace) to find the number of possible matrices.
Concepts Tested
Formulas Used
Matrix multiplication rules
Trace(A) = sum of diagonal elements
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Matrices
- Topic
- Properties of symmetric matrices and matrix multiplication
- Year
- 2021
- Shift
- 26 Feb Shift 1
- Q Number
- Q69
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 3: Matrices
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