Mister Exam

Derivative of 1/cos(x)

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
  1   
------
cos(x)
$$\frac{1}{\cos{\left(x \right)}}$$
1/cos(x)
Detail solution
  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:


The answer is:

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