How to show that Det(A) = 0 without directly evaluating the determinant ? A= first row ( -2 8 1 4 ) second row ( 3 2 5 1 ) third row ( 1 10 6 5 ) and fourth row ( 4 -6 4 -3 )

1 Answer
Sep 16, 2015

Standard Properties of Determinant .

Explanation:

Please go through this link Standard Properties of Determinant

By Theorem DRCMA Determinant for Row or Column Multiples and Addition of Standard Properties of Determinant.

RR_1 ->RR_1 +RR_2 value of det is unchanged here.
RR_1 becomes ( 1 10 6 5 )
RR_3 is ( 1 10 6 5 )

We can see here that corresponding elements in the RR_1 and RR_3 are equal.Hence the rows are equal.

By theorem DERC of the above link if two rows or column are equal
then value of determinant is 0.

Therefore , det(A)=0