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Derivative of cos((pi*x)/2,8)^2

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
   2/pi*x\
cos |----|
    \14/5/
$$\cos^{2}{\left(\frac{\pi x}{\frac{14}{5}} \right)}$$
cos((pi*x)/(14/5))^2
Detail solution
  1. Let .

  2. Apply the power rule: goes to

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

    1. Let .

    2. The derivative of cosine is negative sine:

    3. 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. 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:

        So, the result is:

      The result of the chain rule is:

    The result of the chain rule is:

  4. Now simplify:


The answer is:

The graph
The first derivative [src]
         /pi*x\    /pi*x\
-5*pi*cos|----|*sin|----|
         \14/5/    \14/5/
-------------------------
            7            
$$- \frac{5 \pi \sin{\left(\frac{\pi x}{\frac{14}{5}} \right)} \cos{\left(\frac{\pi x}{\frac{14}{5}} \right)}}{7}$$
The second derivative [src]
     2 /   2/5*pi*x\      2/5*pi*x\\
25*pi *|sin |------| - cos |------||
       \    \  14  /       \  14  //
------------------------------------
                 98                 
$$\frac{25 \pi^{2} \left(\sin^{2}{\left(\frac{5 \pi x}{14} \right)} - \cos^{2}{\left(\frac{5 \pi x}{14} \right)}\right)}{98}$$
The third derivative [src]
      3    /5*pi*x\    /5*pi*x\
125*pi *cos|------|*sin|------|
           \  14  /    \  14  /
-------------------------------
              343              
$$\frac{125 \pi^{3} \sin{\left(\frac{5 \pi x}{14} \right)} \cos{\left(\frac{5 \pi x}{14} \right)}}{343}$$