All positive integral powers of a symmetric matrix are :
Answer & explanation
Correct answer: option 3
Let $A$ be a symmetric matrix, i.e., $A^T = A$
Check $(A^n)^T$ for positive integer $n$:
$(A^n)^T = (A \cdot A \cdot ... \cdot A)^T = A^T \cdot A^T \cdot ... \cdot A^T = A \cdot A \cdot ... \cdot A = A^n$
Thus, $A^n$ is symmetric for all positive integers $n$.
Answer: Symmetric