See above.I'm given his matrix and asked to find the determinant.
Now I do which gives me this
This eliminates the 5th row and 3rd column.
I'm now left with this:
Now I'm trying to get rid of row and column 1:
Awkward says: here you doubled the determinant.
And now I'm left with this:
Now I can solve this and this is what I get:
That gives me:
This is where I don't understand because the answer in the book is 359, but what about the cofactor of 2 when I eliminated the row and column 1?
Don't I have to multiply everything by 2 which would not be the answer in the book?