Answer: Sum of diagonal elements.
- A Sum of all elements
- B Product of diagonal elements
- C Sum of diagonal elements
- D Determinant
Correct answer: C. Sum of diagonal elements
Explanation: The trace of a square matrix is the sum of its main diagonal elements: tr(A) = a<sub>11</sub> + a<sub>22</sub> + ... + ann.
Concept context
Evaluation of determinants, cofactors, adjoint, inverse of matrix, Cramer's rule and area applications. Always in board and JEE.