Q55 of 256 Page 7

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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