1 + cos(2*x) ------------ cos(x)
(1 + cos(2*x))/cos(x)
Apply the quotient rule, which is:
and .
To find :
Differentiate term by term:
The derivative of the constant is zero.
Let .
The derivative of cosine is negative sine:
Then, apply the chain rule. Multiply by :
The derivative of a constant times a function is the constant times the derivative of the function.
Apply the power rule: goes to
So, the result is:
The result of the chain rule is:
The result is:
To find :
The derivative of cosine is negative sine:
Now plug in to the quotient rule:
Now simplify:
The answer is:
2*sin(2*x) (1 + cos(2*x))*sin(x)
- ---------- + ---------------------
cos(x) 2
cos (x)
/ 2 \
| 2*sin (x)| 4*sin(x)*sin(2*x)
-4*cos(2*x) + |1 + ---------|*(1 + cos(2*x)) - -----------------
| 2 | cos(x)
\ cos (x) /
----------------------------------------------------------------
cos(x)
/ 2 \
| 6*sin (x)|
(1 + cos(2*x))*|5 + ---------|*sin(x)
/ 2 \ | 2 |
| 2*sin (x)| 12*cos(2*x)*sin(x) \ cos (x) /
8*sin(2*x) - 6*|1 + ---------|*sin(2*x) - ------------------ + -------------------------------------
| 2 | cos(x) cos(x)
\ cos (x) /
----------------------------------------------------------------------------------------------------
cos(x)