Notes
- 
It's a scalar value that is a function of the entries of a square matrix.
 - 
It represents the area of the parallelogram defined by the vector columns of the matrix.
 - 
If the value is , then:
- the column vectors are linearly dependent.
 
 - 
If the value is not , then:
- the column vectors are linearly independent;
 - the matrix is invertible.
 
 
Questions
- In one sentence, shows that .