HELP PLEASE (( matrix))

how can i find the determinants of a matrix ( 3*3) without inbuild functions (det)

thank u

Answer 1

[Ameer Hamza]

You can just use the formula for determinant

A = rand(3);

d = A(1,1)*(A(2,2)*A(3,3)-A(3,2)*A(2,3)) ...
    -A(1,2)*(A(2,1)*A(3,3)-A(3,1)*A(2,3)) ...
    +A(1,3)*(A(2,1)*A(3,2)-A(3,1)*A(2,2));

Check if it is correct

>> abs(d-det(A))
ans =
   3.4694e-18

A very tiny difference is caused by numerical error.