If 
, write the value of x.
We are given that,
We need to find the value of x.
Determinant of 3 × 3 matrices is found as,
So,
Using trigonometric identity,
sin2 θ + cos2 θ = 1
Since,
⇒ -x3 = 8
⇒ x3 = -8
⇒ x3 = -2 × -2 × -2
Taking cube root on both sides,
⇒ x = -2
Thus, the value of x is -2.
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