/ z \
z*cos|-----|
\z + 1/
z*cos(z/(z + 1))
Apply the product rule:
; to find :
Apply the power rule: goes to
; to find :
Let .
The derivative of cosine is negative sine:
Then, apply the chain rule. Multiply by :
Apply the quotient rule, which is:
and .
To find :
Apply the power rule: goes to
To find :
Differentiate term by term:
The derivative of the constant is zero.
Apply the power rule: goes to
The result is:
Now plug in to the quotient rule:
The result of the chain rule is:
The result is:
Now simplify:
The answer is:
/ 1 z \ / z \ / z \
- z*|----- - --------|*sin|-----| + cos|-----|
|z + 1 2| \z + 1/ \z + 1/
\ (z + 1) /
/ / / z \ / z \ / z \\\
| z*|2*sin|-----| + |-1 + -----|*cos|-----|||
/ z \ | / z \ \ \1 + z/ \ 1 + z/ \1 + z//|
|-1 + -----|*|2*sin|-----| - ------------------------------------------|
\ 1 + z/ \ \1 + z/ 1 + z /
------------------------------------------------------------------------
1 + z
/ / 2 \\
| | / z \ / z \ / z \ / z \ / z \||
| z*|6*sin|-----| - |-1 + -----| *sin|-----| + 6*|-1 + -----|*cos|-----|||
/ z \ | / z \ / z \ / z \ \ \1 + z/ \ 1 + z/ \1 + z/ \ 1 + z/ \1 + z//|
|-1 + -----|*|- 6*sin|-----| - 3*|-1 + -----|*cos|-----| + -----------------------------------------------------------------------|
\ 1 + z/ \ \1 + z/ \ 1 + z/ \1 + z/ 1 + z /
-----------------------------------------------------------------------------------------------------------------------------------
2
(1 + z)