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Derivative of (1)/((cos^2)*x)

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
    1    
---------
   2     
cos (x)*x
$$\frac{1}{x \cos^{2}{\left(x \right)}}$$
1/(cos(x)^2*x)
Detail solution
  1. Let .

  2. Apply the power rule: goes to

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

    1. Apply the product rule:

      ; to find :

      1. Let .

      2. Apply the power rule: goes to

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

        1. The derivative of cosine is negative sine:

        The result of the chain rule is:

      ; to find :

      1. Apply the power rule: goes to

      The result is:

    The result of the chain rule is:

  4. Now simplify:


The answer is:

The graph
The first derivative [src]
    1     /     2                       \
---------*\- cos (x) + 2*x*cos(x)*sin(x)/
     2                                   
x*cos (x)                                
-----------------------------------------
                     2                   
                x*cos (x)                
$$\frac{\frac{1}{x \cos^{2}{\left(x \right)}} \left(2 x \sin{\left(x \right)} \cos{\left(x \right)} - \cos^{2}{\left(x \right)}\right)}{x \cos^{2}{\left(x \right)}}$$
The second derivative [src]
                                                                   /     2           2                     \                                  
/  1   2*sin(x)\                          -cos(x) + 2*x*sin(x)   2*\x*cos (x) - x*sin (x) + 2*cos(x)*sin(x)/   2*(-cos(x) + 2*x*sin(x))*sin(x)
|- - + --------|*(-cos(x) + 2*x*sin(x)) - -------------------- + ------------------------------------------- + -------------------------------
\  x    cos(x) /                                   x                                cos(x)                                  cos(x)            
----------------------------------------------------------------------------------------------------------------------------------------------
                                                                   2    3                                                                     
                                                                  x *cos (x)                                                                  
$$\frac{\left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \left(\frac{2 \sin{\left(x \right)}}{\cos{\left(x \right)}} - \frac{1}{x}\right) + \frac{2 \left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \sin{\left(x \right)}}{\cos{\left(x \right)}} + \frac{2 \left(- x \sin^{2}{\left(x \right)} + x \cos^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \cos{\left(x \right)}\right)}{\cos{\left(x \right)}} - \frac{2 x \sin{\left(x \right)} - \cos{\left(x \right)}}{x}}{x^{2} \cos^{3}{\left(x \right)}}$$
The third derivative [src]
                                                                                                                                                                 /  1   2*sin(x)\                                                                          /  1   2*sin(x)\ /     2           2                     \                                                                                                                                 /  1   2*sin(x)\                              
              /       2           2                       \                            /              2              \                                           |- - + --------|*(-cos(x) + 2*x*sin(x))     /     2           2                     \   2*|- - + --------|*\x*cos (x) - x*sin (x) + 2*cos(x)*sin(x)/         2                                /     2           2                     \                                            2*|- - + --------|*(-cos(x) + 2*x*sin(x))*sin(x)
            2*\- 3*cos (x) + 3*sin (x) + 4*x*cos(x)*sin(x)/                            |    1    3*sin (x)   2*sin(x)|   3*(-cos(x) + 2*x*sin(x))                \  x    cos(x) /                          6*\x*cos (x) - x*sin (x) + 2*cos(x)*sin(x)/     \  x    cos(x) /                                             10*sin (x)*(-cos(x) + 2*x*sin(x))   12*\x*cos (x) - x*sin (x) + 2*cos(x)*sin(x)/*sin(x)   8*(-cos(x) + 2*x*sin(x))*sin(x)     \  x    cos(x) /                              
-2*cos(x) - ----------------------------------------------- + 2*(-cos(x) + 2*x*sin(x))*|1 + -- + --------- - --------| + ------------------------ + 4*x*sin(x) - --------------------------------------- - ------------------------------------------- + ------------------------------------------------------------ + --------------------------------- + --------------------------------------------------- - ------------------------------- + ------------------------------------------------
                                 cos(x)                                                |     2       2       x*cos(x)|               2                                              x                                        x*cos(x)                                               cos(x)                                              2                                            2                                        x*cos(x)                                   cos(x)                     
                                                                                       \    x     cos (x)            /              x                                                                                                                                                                                                cos (x)                                      cos (x)                                                                                                           
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                              2    3                                                                                                                                                                                                                                                
                                                                                                                                                                                                                                             x *cos (x)                                                                                                                                                                                                                                             
$$\frac{4 x \sin{\left(x \right)} + \frac{2 \left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \left(\frac{2 \sin{\left(x \right)}}{\cos{\left(x \right)}} - \frac{1}{x}\right) \sin{\left(x \right)}}{\cos{\left(x \right)}} + 2 \left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \left(\frac{3 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 1 - \frac{2 \sin{\left(x \right)}}{x \cos{\left(x \right)}} + \frac{1}{x^{2}}\right) + \frac{10 \left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + \frac{2 \left(\frac{2 \sin{\left(x \right)}}{\cos{\left(x \right)}} - \frac{1}{x}\right) \left(- x \sin^{2}{\left(x \right)} + x \cos^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \cos{\left(x \right)}\right)}{\cos{\left(x \right)}} + \frac{12 \left(- x \sin^{2}{\left(x \right)} + x \cos^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \cos{\left(x \right)}\right) \sin{\left(x \right)}}{\cos^{2}{\left(x \right)}} - \frac{2 \left(4 x \sin{\left(x \right)} \cos{\left(x \right)} + 3 \sin^{2}{\left(x \right)} - 3 \cos^{2}{\left(x \right)}\right)}{\cos{\left(x \right)}} - 2 \cos{\left(x \right)} - \frac{\left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \left(\frac{2 \sin{\left(x \right)}}{\cos{\left(x \right)}} - \frac{1}{x}\right)}{x} - \frac{8 \left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right) \sin{\left(x \right)}}{x \cos{\left(x \right)}} - \frac{6 \left(- x \sin^{2}{\left(x \right)} + x \cos^{2}{\left(x \right)} + 2 \sin{\left(x \right)} \cos{\left(x \right)}\right)}{x \cos{\left(x \right)}} + \frac{3 \left(2 x \sin{\left(x \right)} - \cos{\left(x \right)}\right)}{x^{2}}}{x^{2} \cos^{3}{\left(x \right)}}$$