The rows and columns of determinants have equal rights, that is,
.
Multiplying any row or column of a determinant by a number , multiplies the determinant by that
number:
This means that the common factor of a row (or column) can be taken outside
the sign of a determinant.
Interchanging any two rows (or columns) of a matrix changes the sign
of the determinant:
If a determinant has a zero-row or zero-column then the determinant is
equal to zero:
If a determinant has two rows (or columns) equal then the determinant
is equal to zero:
If two rows (or columns) of a determinant are proportional to each other
then the determinant is equal to zero:
If each element of a row (or column) of a determinant is the sum of two
items then
A determinant holds its value if a row (column) multiplied by a number
is added to another one:
Let A and B
be square matrices of the same order. Then the determinant of the product
is equal to the product of the determinants:
.
The determinant of a triangular matrix is equal to the product of the
diagonal elements:
In particular, the determinant of an identity matrix is equal to unity.
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