Question 1077536
evaluate the determinant (3by3)  
<pre> 
 1 -1  2
-1  2  0
-1  3  1
</pre>
Det = 1*(2*1 - 3*0) + 1*(-1 - 0) + 2*(-3 + 2)
= 2 - 1 - 2
= -1