Math
Determinants.
Definition
The determinant is a scalar value computed from a square matrix that indicates whether the matrix is invertible and describes the scaling factor of the linear transformation it represents. A determinant of zero means the matrix has no inverse.
Examples
Real-world.
- 1 For matrix [[a,b],[c,d]], det = ad - bc
- 2 A 2×2 matrix [[3,1],[2,4]] has determinant 3(4) - 1(2) = 10
- 3 Determinants are used in Cramer's rule to solve systems of equations
Key Fact
For a 2×2 matrix: det[[a,b],[c,d]] = ad - bc