Let .
The derivative of sine is cosine:
Then, apply the chain rule. Multiply by :
The derivative of a constant times a function is the constant times the derivative of the function.
Apply the power rule: goes to
So, the result is:
The result of the chain rule is:
Now simplify:
The answer is:
/x\ -sin|-| \4/ -------- 16
/x\ -cos|-| \4/ -------- 64