Mister Exam

Derivative of sqrt(cos(x))

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
  ________
\/ cos(x) 
$$\sqrt{\cos{\left(x \right)}}$$
sqrt(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) 
$$- \frac{\sin{\left(x \right)}}{2 \sqrt{\cos{\left(x \right)}}}$$
The second derivative [src]
 /                   2    \ 
 |    ________    sin (x) | 
-|2*\/ cos(x)  + ---------| 
 |                  3/2   | 
 \               cos   (x)/ 
----------------------------
             4              
$$- \frac{\frac{\sin^{2}{\left(x \right)}}{\cos^{\frac{3}{2}}{\left(x \right)}} + 2 \sqrt{\cos{\left(x \right)}}}{4}$$
The third derivative [src]
 /         2   \        
 |    3*sin (x)|        
-|2 + ---------|*sin(x) 
 |        2    |        
 \     cos (x) /        
------------------------
          ________      
      8*\/ cos(x)       
$$- \frac{\left(\frac{3 \sin^{2}{\left(x \right)}}{\cos^{2}{\left(x \right)}} + 2\right) \sin{\left(x \right)}}{8 \sqrt{\cos{\left(x \right)}}}$$
The graph
Derivative of sqrt(cos(x))