Question

设行列式(a 3 1; b 0 1;c 2 1)=1 则行列式(a-3 b-3 c-3 ;;5 2 4;1 1 1)等于

Answer 1

a 3 1

b 0 1 =1

c 2 1

a-3 b-3 c-3

5 2 4

1 1 1

r1+3r3,r2-2r3

a b c

= 3 0 2

1 1 1

将这个行列式转置

a 3 1

= b 0 1

c 2 1

=1