Mister Exam

Derivative of tgx-ctgx+cosx

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
tan(x) - cot(x) + cos(x)
$$\left(\tan{\left(x \right)} - \cot{\left(x \right)}\right) + \cos{\left(x \right)}$$
Detail solution
  1. Differentiate term by term:

    1. Differentiate term by term:

      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:

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

        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 :

            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:

        So, the result is:

      The result is:

    2. The derivative of cosine is negative sine:

    The result is:

  2. Now simplify:


The answer is:

The graph
The first derivative [src]
       2         2            
2 + cot (x) + tan (x) - sin(x)
$$- \sin{\left(x \right)} + \tan^{2}{\left(x \right)} + \cot^{2}{\left(x \right)} + 2$$
The second derivative [src]
            /       2   \            /       2   \       
-cos(x) - 2*\1 + cot (x)/*cot(x) + 2*\1 + tan (x)/*tan(x)
$$2 \left(\tan^{2}{\left(x \right)} + 1\right) \tan{\left(x \right)} - 2 \left(\cot^{2}{\left(x \right)} + 1\right) \cot{\left(x \right)} - \cos{\left(x \right)}$$
The third derivative [src]
               2                  2                                                             
  /       2   \      /       2   \         2    /       2   \        2    /       2   \         
2*\1 + cot (x)/  + 2*\1 + tan (x)/  + 4*cot (x)*\1 + cot (x)/ + 4*tan (x)*\1 + tan (x)/ + sin(x)
$$2 \left(\tan^{2}{\left(x \right)} + 1\right)^{2} + 4 \left(\tan^{2}{\left(x \right)} + 1\right) \tan^{2}{\left(x \right)} + 2 \left(\cot^{2}{\left(x \right)} + 1\right)^{2} + 4 \left(\cot^{2}{\left(x \right)} + 1\right) \cot^{2}{\left(x \right)} + \sin{\left(x \right)}$$
The graph
Derivative of tgx-ctgx+cosx