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1/cosx^3

Derivative of 1/cosx^3

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
     1   
1*-------
     3   
  cos (x)
$$1 \cdot \frac{1}{\cos^{3}{\left(x \right)}}$$
d /     1   \
--|1*-------|
dx|     3   |
  \  cos (x)/
$$\frac{d}{d x} 1 \cdot \frac{1}{\cos^{3}{\left(x \right)}}$$
Detail solution
  1. Apply the quotient rule, which is:

    and .

    To find :

    1. The derivative of the constant is zero.

    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:

    Now plug in to the quotient rule:


The answer is:

The graph
The first derivative [src]
   3*sin(x)   
--------------
          3   
cos(x)*cos (x)
$$\frac{3 \sin{\left(x \right)}}{\cos{\left(x \right)} \cos^{3}{\left(x \right)}}$$
The second derivative [src]
  /         2   \
  |    4*sin (x)|
3*|1 + ---------|
  |        2    |
  \     cos (x) /
-----------------
        3        
     cos (x)     
$$\frac{3 \cdot \left(\frac{4 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 1\right)}{\cos^{3}{\left(x \right)}}$$
The third derivative [src]
  /           2   \       
  |     20*sin (x)|       
3*|11 + ----------|*sin(x)
  |         2     |       
  \      cos (x)  /       
--------------------------
            4             
         cos (x)          
$$\frac{3 \cdot \left(\frac{20 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 11\right) \sin{\left(x \right)}}{\cos^{4}{\left(x \right)}}$$
The graph
Derivative of 1/cosx^3