Let .
Apply the power rule: goes to
Then, apply the chain rule. Multiply by :
Rewrite the function to be differentiated:
Apply the quotient rule, which is:
and .
To find :
The derivative of sine is cosine:
To find :
The derivative of cosine is negative sine:
Now plug in to the quotient rule:
The result of the chain rule is:
Now simplify:
The answer is:
/ 2 \ / 2 \ | 3 ________ 1 + tan (x)| 2*\1 + tan (x)/*|3*\/ tan(x) - -----------| | 5/3 | \ tan (x) / -------------------------------------------- 9