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Derivative of 1/2*ctg^2x+ln(sinx)

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

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Piecewise:

The solution

You have entered [src]
   2                 
cot (x)              
------- + log(sin(x))
   2                 
$$\log{\left(\sin{\left(x \right)} \right)} + \frac{\cot^{2}{\left(x \right)}}{2}$$
cot(x)^2/2 + log(sin(x))
Detail solution
  1. Differentiate term by term:

    1. The derivative of a constant times a function is the constant times the derivative of the function.

      1. Let .

      2. Apply the power rule: goes to

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

        1. There are multiple ways to do this derivative.

          Method #1

          1. Rewrite the function to be differentiated:

          2. Let .

          3. Apply the power rule: goes to

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

            1. Rewrite the function to be differentiated:

            2. Apply the quotient rule, which is:

              and .

              To find :

              1. The derivative of sine is cosine:

              To find :

              1. The derivative of cosine is negative sine:

              Now plug in to the quotient rule:

            The result of the chain rule is:

          Method #2

          1. Rewrite the function to be differentiated:

          2. Apply the quotient rule, which is:

            and .

            To find :

            1. The derivative of cosine is negative sine:

            To find :

            1. The derivative of sine is cosine:

            Now plug in to the quotient rule:

        The result of the chain rule is:

      So, the result is:

    2. Let .

    3. The derivative of is .

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

      1. The derivative of sine is cosine:

      The result of the chain rule is:

    The result is:

  2. Now simplify:


The answer is:

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