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

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Answer 1 · 2016-07-10T16:14:00

You can not manipulate this matrix into the form

$[(1,0,0),(0,1,0),(0,0,1)]$

So it does not have a determinate

$[(1,-1,2" | " 1,0,0),(0,3,0" | "0,1,0),(1,2,2" | "0,0,1)]$
$Row(2)-:3$
$" "darr$
$color(white)(.)$

$[(1,-1,2" | " 1,0,0),(0,1,0" | "0,1/3,0),(1,2,2" | "0,0,1)]$
$Row(3)-Row(1)$
$" "darr$
$color(white)(.)$

$[(1,-1,2" | " 1,0,0),(0,1,0" | "0,1/3,0),(0,3,0" | "-1,0,1)]$
$Row(3)-Row(1)$
$" "darr$
$color(white)(.)$

You can not manipulate this matrix into the form

$[(1,0,0),(0,1,0),(0,0,1)]$

So it does not have a determinate

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