[ruslan_mart]

<script>
function Determinant(A)
{  
    var n = A.length, subA = [], detA = 0;
        
    if (n==1) return A[0][0];
    if (n==2) return (A[0][0]*A[1][1]-A[0][1]*A[1][0]);
    if (n==3)
       { return ((A[0][0]*A[1][1]*A[2][2]+A[0][1]*A[1][2]*A[2][0]+A[0][2]*A[1][0]*A[2][1])
                 -(A[0][0]*A[1][2]*A[2][1]+A[0][1]*A[1][0]*A[2][2]+A[0][2]*A[1][1]*A[2][0]));
       }

    for (var i=0; i<n; i++)
        { for (var h=0; h<n-1; h++) subA[h]=[];
          for (var a=1; a<n; a++)
              { for (var b=0; b<n; b++)
                    { if (b<i)       subA[a-1][ b ] = A[ a ][ b ];
                      else if (b>i)  subA[a-1][b-1] = A[ a ][ b ];
                    }
              }
          var sign = (i%2==0) ? 1 : -1;
          detA += sign * A[0][i] * Determinant(subA);
        }

    return detA;
}

document.write(Determinant(тут ваша матрица));
</script>