Question

How do you find the determinant of `((2, -2, 2), (1, 2, 4), (3, 0, 5))`?

Answer 1

I found `-6`

Explanation:

I would add the first line to the second to get:
`((2,-2,2),(3,0,6),(3,0,5))`
I would then cancel the first line and second row maintaining the intersection corresponding to `-2` and a minus sign corresponding to its position in the sequence:
`((+,-,+),(-,+,-),(+,-,+))`
getting:
`color(red)(-)(color(blue)(-2))((3,6),(3,5))`
or:
`2((3,6),(3,5))`
and a determinant of:
`2[(3*5)-(6*3)]=-6`