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