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 1 tan (x) - + ------- 3 3 ----------- 2/3 tan (x)
/ 2 \ / 2 \ | 3 ________ 1 + tan (x)| 2*\1 + tan (x)/*|3*\/ tan(x) - -----------| | 5/3 | \ tan (x) / -------------------------------------------- 9
/ 2\ | / 2 \ / 2 \ | / 2 \ | 4/3 9*\1 + tan (x)/ 5*\1 + tan (x)/ | 2*\1 + tan (x)/*|18*tan (x) - --------------- + ----------------| | 2/3 8/3 | \ tan (x) tan (x) / ------------------------------------------------------------------- 27