The Determinant
The definition of the determinant of a matrix is something we will not need in this course. What we will need is to use the determinant. Here are some examples of computations.
a={{a11, a12},{a21, a22}}
Det[a]
b={{b11, b12, b13},{b21, b22, b23},{b31, b32, b33}}
Det[b]
c={{2, 1, 0, 1},{3, 2, 1, 2},{4, 0, 1, 4},{1, 0, 2, 1}}
Det[c]
Up to Two Important Functions of a Matrix