Mark the Correct alternative in the following:
The value of 
is
Given expression is 
[using the identity sin2 x + cos2 x = 1]
[using the formula a2 + b2 = (a + b)2 – 2ab]
[ using the sum of angle formula 
]
[Using the identity cos (A+B) – cos (A-B) = -2sinAsinB ]
[multiplying and dividing the term cos2 x with 2]
[using the cos 2θ = 2cos2 θ – 1]
Hence the answer is option A.
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