Introducing the matrix determinant
The determinant of a matrix is a special scalar value that can be calculated from a matrix. Here, the matrix needs to be square, meaning it has an equal number of rows and columns. For a 2x2 square matrix, the determinant is simply calculated as the difference between the product of the diagonal elements and the off-diagonal elements.
Mathematically, suppose our 2x2 matrix is A = [a b c d ]. Its determinant, |A|, is thus calculated as follows:
det(A) = |A| = ad − bc
Please do not confuse these vertical lines with the absolute operation sign. They represent the determinant in the context of a matrix, and the determinant of a matrix can be negative as well.
Let’s say our 2x2 matrix is A = [2 6 1 8]. We can find its determinant like so:
|A| = 2 * 8 − 6 * 1 = 10
Calculating the determinant of a matrix is the easy part, but understanding its use is of equal importance. Before we...
