The value of (3≤ft(1-2 sin ^2 x))/(cos ^2 x-sin ^2 x) is:

$\frac{3\left(1-2 \sin ^2 x\right)}{\cos ^2 x-\sin ^2 x}$

= \(\frac{3 ( 1 - 2sin²x )}{cos²x - sin²x}\)

= \(\frac{3 ( 1 - sin²x  - sin²x)}{cos²x - sin²x}\)

{ sin²A + cos²A = 1 }

= \(\frac{3 ( cos²x  - sin²x)}{cos²x - sin²x}\)

= 3