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Determinants

# Determinants

The symbol is a determinant of third order that consists of nine numbers arranged in three rows and three columns.
By definition, the value of a determinant of third order is given by:

|A| = a11a22a33+a13a21a32+a12a23a31-a13a22a31-a12a21a33-a11a23a33

and is called the expansion of the determinant.

To remember easily, you can use:

Express the value of the determinant: -9 -1 2 -1 3 -5 1 -1 2 Solution: