3×3 Determinant Calculator — Upper-Triangular Pivot Reduction & Sign Tracking
Computes exact determinant via Gaussian elimination while tracking row-swap parity (−1)^s and parallelepiped volume orientation.
Pre-Verified Algebraic Summary
Related Step-by-Step Matrix Solvers
Transforms any matrix into canonical Reduced Row Echelon Form using exact GCD-simplified rational elementary row operations.
3×4 · RREF
Solves 2x₁ + x₂ − x₃ = 8, −3x₁ − x₂ + 2x₃ = −11, −2x₁ + x₂ + 2x₃ = −3 to exact solution (2, 3, −1) with zero residual.
3×3 · SYSTEM
Solves diagonally dominant 4-node steady-state Laplace finite-difference / resistor mesh equations with exact rational fractions.
4×4 · SYSTEM
Identifies pivot vs. free variables when rank(A) = rank([A|b]) < n and constructs full vector solution x = x_p + t₁v₁ + t₂v₂.
3×4 · SYSTEM
Demonstrates step-by-step how rank(A) < rank([A|b]) produces an explicit contradiction row 0 = 4, proving zero solutions exist.
3×3 · SYSTEM
Avoids 24-term Leibniz cofactor expansion by reducing 4×4 matrices cleanly to four exact rational diagonal pivots.
4×4 · DET
Mathematical Reference & Frequently Asked Questions
Can I edit the entries or dimensions of this benchmark matrix?
Yes. Edit any cell (integers, decimals, or fractions like -3/4) or switch operations to recompute all row-reduction steps live.