What Is Determinant?
The determinant is a single number computed from a square matrix that reveals whether the matrix has an inverse (a determinant of 0 means it doesn't) and, geometrically, how much a transformation described by the matrix scales area or volume. It's a required step in finding a matrix's inverse.
Example
For the 2×2 matrix [[1, 2], [3, 4]], the determinant is (1×4) − (2×3) = 4 − 6 = −2.