Let .
The derivative of is .
Then, apply the chain rule. Multiply by :
Differentiate term by term:
Apply the power rule: goes to
The derivative of the constant is zero.
The result is:
The result of the chain rule is:
Now simplify:
The answer is:
/ 2 \
| 2*x |
2*|1 - ------|
| 2|
\ 4 + x /
--------------
2
4 + x
/ 2 \
| 4*x |
4*x*|-3 + ------|
| 2|
\ 4 + x /
-----------------
2
/ 2\
\4 + x /