Determinant of a 4x4 matrix? - Answers

The determinant of a 4x4 matrix can be calculated using various methods, including cofactor expansion or row reduction. The cofactor expansion involves selecting a row or column, multiplying each element by its corresponding cofactor, and summing the results. Alternatively, row reduction can simplify the matrix to an upper triangular form, where the determinant is the product of the diagonal elements, adjusted for any row swaps. The determinant provides important information about the matrix, such as whether it is invertible (non-zero determinant) or singular (zero determinant).