Apply the quotient rule, which is:
and .
To find :
The derivative of is itself.
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:
Now simplify:
The answer is:
x x
e e
----- - --------
1 + x 2
(1 + x)
/ 2 2 \ x
|1 - ----- + --------|*e
| 1 + x 2|
\ (1 + x) /
-------------------------
1 + x
/ 6 3 6 \ x
|1 - -------- - ----- + --------|*e
| 3 1 + x 2|
\ (1 + x) (1 + x) /
------------------------------------
1 + x