I think I was handed a trick question.
For the matrix , use Cramer's Rule to find when .
My current answer is . Is this correct, or do I have to determine what is by inverting ?
Have a look at Online Matrix Calculator
I say it because I believe that by stating , it could mean that you need to do this: , before you apply Cramer's Rule. This would come out to , and this would be used in Cramer's Rule, not .
Of course, I could be wrong. That's why I thought this might be a trick question.