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