Worked example

a: 1	2
3	4

→ −2

Method and scope

Square matrices only. Gaussian elimination with partial pivoting uses cubic work rather than cofactor expansion. Every row swap flips the determinant sign. Floating-point cancellation near singularity can affect the answer.

det(A) = det(P) × ∏ Uᵢᵢ; det(P) ∈ {−1,+1}

Precision and limits

≈ marks an approximation. Display rounding does not change the internal calculation.

Sources