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Derivative of lncos(2x-1/7)+2

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

The graph:

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The solution

You have entered [src]
log(cos(2*x - 1/7)) + 2
$$\log{\left(\cos{\left(2 x - \frac{1}{7} \right)} \right)} + 2$$
log(cos(2*x - 1/7)) + 2
Detail solution
  1. Differentiate term by term:

    1. Let .

    2. The derivative of is .

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

      1. Let .

      2. The derivative of cosine is negative sine:

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

        1. Differentiate term by term:

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

            1. Apply the power rule: goes to

            So, the result is:

          2. The derivative of the constant is zero.

          The result is:

        The result of the chain rule is:

      The result of the chain rule is:

    4. The derivative of the constant is zero.

    The result is:

  2. Now simplify:


The answer is:

The graph
The first derivative [src]
-2*sin(2*x - 1/7)
-----------------
  cos(2*x - 1/7) 
$$- \frac{2 \sin{\left(2 x - \frac{1}{7} \right)}}{\cos{\left(2 x - \frac{1}{7} \right)}}$$
The second derivative [src]
   /       2            \
   |    sin (-1/7 + 2*x)|
-4*|1 + ----------------|
   |       2            |
   \    cos (-1/7 + 2*x)/
$$- 4 \left(\frac{\sin^{2}{\left(2 x - \frac{1}{7} \right)}}{\cos^{2}{\left(2 x - \frac{1}{7} \right)}} + 1\right)$$
The third derivative [src]
    /       2            \                
    |    sin (-1/7 + 2*x)|                
-16*|1 + ----------------|*sin(-1/7 + 2*x)
    |       2            |                
    \    cos (-1/7 + 2*x)/                
------------------------------------------
             cos(-1/7 + 2*x)              
$$- \frac{16 \left(\frac{\sin^{2}{\left(2 x - \frac{1}{7} \right)}}{\cos^{2}{\left(2 x - \frac{1}{7} \right)}} + 1\right) \sin{\left(2 x - \frac{1}{7} \right)}}{\cos{\left(2 x - \frac{1}{7} \right)}}$$