The Determinant of a Matrix

A single number that captures important information about a square matrix.

Determinant of a 2x2 Matrix

For $A = \begin{pmatrix} a & b \\ c & d \end{pmatrix}$:

$$|A| = ad - bc$$

Determinant of a 3x3 Matrix

Calculated by expansion along any row or column, using cofactors.

Lesson 8 of 32
On This Page