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Derivative of (1+cos2x)/cosx

Function f() - derivative -N order at the point
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
1 + cos(2*x)
------------
   cos(x)   
$$\frac{\cos{\left(2 x \right)} + 1}{\cos{\left(x \right)}}$$
(1 + cos(2*x))/cos(x)
Detail solution
  1. Apply the quotient rule, which is:

    and .

    To find :

    1. Differentiate term by term:

      1. The derivative of the constant is zero.

      2. Let .

      3. The derivative of cosine is negative sine:

      4. Then, apply the chain rule. Multiply by :

        1. The derivative of a constant times a function is the constant times the derivative of the function.

          1. Apply the power rule: goes to

          So, the result is:

        The result of the chain rule is:

      The result is:

    To find :

    1. The derivative of cosine is negative sine:

    Now plug in to the quotient rule:

  2. Now simplify:


The answer is:

The graph
The first derivative [src]
  2*sin(2*x)   (1 + cos(2*x))*sin(x)
- ---------- + ---------------------
    cos(x)               2          
                      cos (x)       
$$\frac{\left(\cos{\left(2 x \right)} + 1\right) \sin{\left(x \right)}}{\cos^{2}{\left(x \right)}} - \frac{2 \sin{\left(2 x \right)}}{\cos{\left(x \right)}}$$
The second derivative [src]
              /         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)                             
$$\frac{\left(\frac{2 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 1\right) \left(\cos{\left(2 x \right)} + 1\right) - \frac{4 \sin{\left(x \right)} \sin{\left(2 x \right)}}{\cos{\left(x \right)}} - 4 \cos{\left(2 x \right)}}{\cos{\left(x \right)}}$$
The third derivative [src]
                                                                              /         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)                                               
$$\frac{- 6 \left(\frac{2 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 1\right) \sin{\left(2 x \right)} + \frac{\left(\frac{6 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 5\right) \left(\cos{\left(2 x \right)} + 1\right) \sin{\left(x \right)}}{\cos{\left(x \right)}} - \frac{12 \sin{\left(x \right)} \cos{\left(2 x \right)}}{\cos{\left(x \right)}} + 8 \sin{\left(2 x \right)}}{\cos{\left(x \right)}}$$