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Derivative of (z/(1-cosz))(z-2*pi*k)²

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

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Piecewise:

The solution

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

    and .

    To find :

    1. Apply the product rule:

      ; to find :

      1. Apply the power rule: goes to

      ; to find :

      1. Let .

      2. Apply the power rule: goes to

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

        1. Differentiate term by term:

          1. Apply the power rule: goes to

          2. The derivative of the constant is zero.

          The result is:

        The result of the chain rule is:

      The result is:

    To find :

    1. Differentiate term by term:

      1. The derivative of the constant is zero.

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

        1. The derivative of cosine is negative sine:

        So, the result is:

      The result is:

    Now plug in to the quotient rule:

  2. Now simplify:


The answer is:

The first derivative [src]
            2 /    1           z*sin(z)  \   z*(2*z - 4*pi*k)
(z - 2*pi*k) *|---------- - -------------| + ----------------
              |1 - cos(z)               2|      1 - cos(z)   
              \             (1 - cos(z)) /                   
$$\frac{z \left(- 4 \pi k + 2 z\right)}{1 - \cos{\left(z \right)}} + \left(- 2 \pi k + z\right)^{2} \left(- \frac{z \sin{\left(z \right)}}{\left(1 - \cos{\left(z \right)}\right)^{2}} + \frac{1}{1 - \cos{\left(z \right)}}\right)$$
The second derivative [src]
                                                          /             /      2             \\
                                                        2 |             | 2*sin (z)          ||
                                           (-z + 2*pi*k) *|2*sin(z) + z*|----------- + cos(z)||
         /      z*sin(z) \                                \             \-1 + cos(z)         //
-2*z + 4*|1 + -----------|*(-z + 2*pi*k) - ----------------------------------------------------
         \    -1 + cos(z)/                                     -1 + cos(z)                     
-----------------------------------------------------------------------------------------------
                                          -1 + cos(z)                                          
$$\frac{- 2 z - \frac{\left(2 \pi k - z\right)^{2} \left(z \left(\cos{\left(z \right)} + \frac{2 \sin^{2}{\left(z \right)}}{\cos{\left(z \right)} - 1}\right) + 2 \sin{\left(z \right)}\right)}{\cos{\left(z \right)} - 1} + 4 \left(2 \pi k - z\right) \left(\frac{z \sin{\left(z \right)}}{\cos{\left(z \right)} - 1} + 1\right)}{\cos{\left(z \right)} - 1}$$
The third derivative [src]
                    /                 2         /                          2      \       \                                                                      
                  2 |            6*sin (z)      |       6*cos(z)      6*sin (z)   |       |                                 /             /      2             \\
     (-z + 2*pi*k) *|3*cos(z) + ----------- + z*|-1 + ----------- + --------------|*sin(z)|                                 |             | 2*sin (z)          ||
                    |           -1 + cos(z)     |     -1 + cos(z)                2|       |                 6*(-z + 2*pi*k)*|2*sin(z) + z*|----------- + cos(z)||
                    \                           \                   (-1 + cos(z)) /       /    6*z*sin(z)                   \             \-1 + cos(z)         //
-6 - -------------------------------------------------------------------------------------- - ----------- + -----------------------------------------------------
                                          -1 + cos(z)                                         -1 + cos(z)                        -1 + cos(z)                     
-----------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           -1 + cos(z)                                                                           
$$\frac{- \frac{6 z \sin{\left(z \right)}}{\cos{\left(z \right)} - 1} - \frac{\left(2 \pi k - z\right)^{2} \left(z \left(-1 + \frac{6 \cos{\left(z \right)}}{\cos{\left(z \right)} - 1} + \frac{6 \sin^{2}{\left(z \right)}}{\left(\cos{\left(z \right)} - 1\right)^{2}}\right) \sin{\left(z \right)} + 3 \cos{\left(z \right)} + \frac{6 \sin^{2}{\left(z \right)}}{\cos{\left(z \right)} - 1}\right)}{\cos{\left(z \right)} - 1} + \frac{6 \left(2 \pi k - z\right) \left(z \left(\cos{\left(z \right)} + \frac{2 \sin^{2}{\left(z \right)}}{\cos{\left(z \right)} - 1}\right) + 2 \sin{\left(z \right)}\right)}{\cos{\left(z \right)} - 1} - 6}{\cos{\left(z \right)} - 1}$$