What is a square matrix?

What is a square matrix?

• A. Matrix with more columns than rows.
• B. Matrix with more rows than columns.
• C. Matrix with equal number of rows and columns.
• D. Matrix with variable row and column counts.

Answer: (C)

A square matrix has the same number of rows and columns, forming a square block of numbers. In notation, it’s an m by m matrix. Examples include 3x3 or 5x5. If there are more columns than rows or more rows than columns, or if the dimensions vary, it isn’t square. This shape matters because many important concepts—like determinants, inverses (when the determinant isn’t zero), and eigenvalues—are defined specifically for square matrices.

A square matrix has the same number of rows and columns, forming a square block of numbers. In notation, it’s an m by m matrix. Examples include 3x3 or 5x5. If there are more columns than rows or more rows than columns, or if the dimensions vary, it isn’t square. This shape matters because many important concepts—like determinants, inverses (when the determinant isn’t zero), and eigenvalues—are defined specifically for square matrices.