Which elementary operation is NOT valid when finding the inverse of a matrix?

Which elementary operation is NOT valid when finding the inverse of a matrix?

• A. Interchanging two rows
• B. Multiplying a row by a non-zero scalar
• C. Adding a multiple of one row to another row
• D. Multiplying two rows together

Answer: D) Multiplying two rows together

Explanation: Valid elementary row operations include row swapping, scaling a row by a non-zero constant, and row addition. Multiplying two rows together is not a valid elementary operation.