Mister Exam

Derivative of cos(log(x))

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
cos(log(x))
cos(log(x))\cos{\left(\log{\left(x \right)} \right)}
cos(log(x))
Detail solution
  1. Let u=log(x)u = \log{\left(x \right)}.

  2. The derivative of cosine is negative sine:

    dducos(u)=sin(u)\frac{d}{d u} \cos{\left(u \right)} = - \sin{\left(u \right)}

  3. Then, apply the chain rule. Multiply by ddxlog(x)\frac{d}{d x} \log{\left(x \right)}:

    1. The derivative of log(x)\log{\left(x \right)} is 1x\frac{1}{x}.

    The result of the chain rule is:

    sin(log(x))x- \frac{\sin{\left(\log{\left(x \right)} \right)}}{x}


The answer is:

sin(log(x))x- \frac{\sin{\left(\log{\left(x \right)} \right)}}{x}

The graph
02468-8-6-4-2-1010-1010
The first derivative [src]
-sin(log(x)) 
-------------
      x      
sin(log(x))x- \frac{\sin{\left(\log{\left(x \right)} \right)}}{x}
The second derivative [src]
-cos(log(x)) + sin(log(x))
--------------------------
             2            
            x             
sin(log(x))cos(log(x))x2\frac{\sin{\left(\log{\left(x \right)} \right)} - \cos{\left(\log{\left(x \right)} \right)}}{x^{2}}
The third derivative [src]
-sin(log(x)) + 3*cos(log(x))
----------------------------
              3             
             x              
sin(log(x))+3cos(log(x))x3\frac{- \sin{\left(\log{\left(x \right)} \right)} + 3 \cos{\left(\log{\left(x \right)} \right)}}{x^{3}}
The graph
Derivative of cos(log(x))