Final answer:
The determinant of a 2x2 matrix [ ac bd] is calculated as ad−bc. For the matrix [ 5/4, 1; -1, -4/5], the determinant is -21/5.
Step-by-step explanation:
To find the determinant of a 2x2 matrix:
Matrix=[ a c b d]
The determinant (det) is calculated as:
det = ad−bc
For the given matrix:
[5/4 -1 1 4/5 ]
The determinant (det) is:
det = ( 5/4 * -4/5) - (1*-1)
Simplify this expression to find the determinant.