If A = \(\left[\begin{array}{cc} 1 & \tan x \\ -\tan x & 1 \end{array}\right]\),
then the value of |A' A–1| is
1
cos 4x
2
sec2 x
3
– cos 4x
4
1
If A = \(\left[\begin{array}{cc} 1 & \tan x \\ -\tan x & 1 \end{array}\right]\),
then the value of |A' A–1| is