The function is $\"\"$ .

Apply derivative on each side with respect to $\"\"$ .

$\"\"$

Difference rule of derivatives: $\"\"$ .

$\"\"$

Constant multiple rule of derivatives: $\"\"$ .

$\"\"$

Power rule of derivatives: $\"\"$

Derivative of a cosine function: $\"\"$ .

$\"\"$

$\"\"$ .

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