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y=ln(ctg2x^3)

Derivative of y=ln(ctg2x^3)

Function f() - derivative -N order at the point
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   /   3     \
log\cot (2*x)/
log(cot3(2x))\log{\left(\cot^{3}{\left(2 x \right)} \right)}
log(cot(2*x)^3)
Detail solution
  1. Let u=cot3(2x)u = \cot^{3}{\left(2 x \right)}.

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

  3. Then, apply the chain rule. Multiply by ddxcot3(2x)\frac{d}{d x} \cot^{3}{\left(2 x \right)}:

    1. Let u=cot(2x)u = \cot{\left(2 x \right)}.

    2. Apply the power rule: u3u^{3} goes to 3u23 u^{2}

    3. Then, apply the chain rule. Multiply by ddxcot(2x)\frac{d}{d x} \cot{\left(2 x \right)}:

      1. There are multiple ways to do this derivative.

        Method #1

        1. Rewrite the function to be differentiated:

          cot(2x)=1tan(2x)\cot{\left(2 x \right)} = \frac{1}{\tan{\left(2 x \right)}}

        2. Let u=tan(2x)u = \tan{\left(2 x \right)}.

        3. Apply the power rule: 1u\frac{1}{u} goes to 1u2- \frac{1}{u^{2}}

        4. Then, apply the chain rule. Multiply by ddxtan(2x)\frac{d}{d x} \tan{\left(2 x \right)}:

          1. Rewrite the function to be differentiated:

            tan(2x)=sin(2x)cos(2x)\tan{\left(2 x \right)} = \frac{\sin{\left(2 x \right)}}{\cos{\left(2 x \right)}}

          2. Apply the quotient rule, which is:

            ddxf(x)g(x)=f(x)ddxg(x)+g(x)ddxf(x)g2(x)\frac{d}{d x} \frac{f{\left(x \right)}}{g{\left(x \right)}} = \frac{- f{\left(x \right)} \frac{d}{d x} g{\left(x \right)} + g{\left(x \right)} \frac{d}{d x} f{\left(x \right)}}{g^{2}{\left(x \right)}}

            f(x)=sin(2x)f{\left(x \right)} = \sin{\left(2 x \right)} and g(x)=cos(2x)g{\left(x \right)} = \cos{\left(2 x \right)}.

            To find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

            1. Let u=2xu = 2 x.

            2. The derivative of sine is cosine:

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

            3. Then, apply the chain rule. Multiply by ddx2x\frac{d}{d x} 2 x:

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

                1. Apply the power rule: xx goes to 11

                So, the result is: 22

              The result of the chain rule is:

              2cos(2x)2 \cos{\left(2 x \right)}

            To find ddxg(x)\frac{d}{d x} g{\left(x \right)}:

            1. Let u=2xu = 2 x.

            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 ddx2x\frac{d}{d x} 2 x:

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

                1. Apply the power rule: xx goes to 11

                So, the result is: 22

              The result of the chain rule is:

              2sin(2x)- 2 \sin{\left(2 x \right)}

            Now plug in to the quotient rule:

            2sin2(2x)+2cos2(2x)cos2(2x)\frac{2 \sin^{2}{\left(2 x \right)} + 2 \cos^{2}{\left(2 x \right)}}{\cos^{2}{\left(2 x \right)}}

          The result of the chain rule is:

          2sin2(2x)+2cos2(2x)cos2(2x)tan2(2x)- \frac{2 \sin^{2}{\left(2 x \right)} + 2 \cos^{2}{\left(2 x \right)}}{\cos^{2}{\left(2 x \right)} \tan^{2}{\left(2 x \right)}}

        Method #2

        1. Rewrite the function to be differentiated:

          cot(2x)=cos(2x)sin(2x)\cot{\left(2 x \right)} = \frac{\cos{\left(2 x \right)}}{\sin{\left(2 x \right)}}

        2. Apply the quotient rule, which is:

          ddxf(x)g(x)=f(x)ddxg(x)+g(x)ddxf(x)g2(x)\frac{d}{d x} \frac{f{\left(x \right)}}{g{\left(x \right)}} = \frac{- f{\left(x \right)} \frac{d}{d x} g{\left(x \right)} + g{\left(x \right)} \frac{d}{d x} f{\left(x \right)}}{g^{2}{\left(x \right)}}

          f(x)=cos(2x)f{\left(x \right)} = \cos{\left(2 x \right)} and g(x)=sin(2x)g{\left(x \right)} = \sin{\left(2 x \right)}.

          To find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

          1. Let u=2xu = 2 x.

          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 ddx2x\frac{d}{d x} 2 x:

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

              1. Apply the power rule: xx goes to 11

              So, the result is: 22

            The result of the chain rule is:

            2sin(2x)- 2 \sin{\left(2 x \right)}

          To find ddxg(x)\frac{d}{d x} g{\left(x \right)}:

          1. Let u=2xu = 2 x.

          2. The derivative of sine is cosine:

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

          3. Then, apply the chain rule. Multiply by ddx2x\frac{d}{d x} 2 x:

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

              1. Apply the power rule: xx goes to 11

              So, the result is: 22

            The result of the chain rule is:

            2cos(2x)2 \cos{\left(2 x \right)}

          Now plug in to the quotient rule:

          2sin2(2x)2cos2(2x)sin2(2x)\frac{- 2 \sin^{2}{\left(2 x \right)} - 2 \cos^{2}{\left(2 x \right)}}{\sin^{2}{\left(2 x \right)}}

      The result of the chain rule is:

      3(2sin2(2x)+2cos2(2x))cot2(2x)cos2(2x)tan2(2x)- \frac{3 \left(2 \sin^{2}{\left(2 x \right)} + 2 \cos^{2}{\left(2 x \right)}\right) \cot^{2}{\left(2 x \right)}}{\cos^{2}{\left(2 x \right)} \tan^{2}{\left(2 x \right)}}

    The result of the chain rule is:

    3(2sin2(2x)+2cos2(2x))cos2(2x)tan2(2x)cot(2x)- \frac{3 \left(2 \sin^{2}{\left(2 x \right)} + 2 \cos^{2}{\left(2 x \right)}\right)}{\cos^{2}{\left(2 x \right)} \tan^{2}{\left(2 x \right)} \cot{\left(2 x \right)}}

  4. Now simplify:

    12sin(4x)- \frac{12}{\sin{\left(4 x \right)}}


The answer is:

12sin(4x)- \frac{12}{\sin{\left(4 x \right)}}

The graph
02468-8-6-4-2-1010-500500
The first derivative [src]
          2     
-6 - 6*cot (2*x)
----------------
    cot(2*x)    
6cot2(2x)6cot(2x)\frac{- 6 \cot^{2}{\left(2 x \right)} - 6}{\cot{\left(2 x \right)}}
The second derivative [src]
   /                                 2\
   |                  /       2     \ |
   |         2        \1 + cot (2*x)/ |
12*|2 + 2*cot (2*x) - ----------------|
   |                        2         |
   \                     cot (2*x)    /
12((cot2(2x)+1)2cot2(2x)+2cot2(2x)+2)12 \left(- \frac{\left(\cot^{2}{\left(2 x \right)} + 1\right)^{2}}{\cot^{2}{\left(2 x \right)}} + 2 \cot^{2}{\left(2 x \right)} + 2\right)
The third derivative [src]
                   /                             2                    \
                   |              /       2     \      /       2     \|
   /       2     \ |              \1 + cot (2*x)/    2*\1 + cot (2*x)/|
48*\1 + cot (2*x)/*|-2*cot(2*x) - ---------------- + -----------------|
                   |                    3                 cot(2*x)    |
                   \                 cot (2*x)                        /
48(cot2(2x)+1)((cot2(2x)+1)2cot3(2x)+2(cot2(2x)+1)cot(2x)2cot(2x))48 \left(\cot^{2}{\left(2 x \right)} + 1\right) \left(- \frac{\left(\cot^{2}{\left(2 x \right)} + 1\right)^{2}}{\cot^{3}{\left(2 x \right)}} + \frac{2 \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\cot{\left(2 x \right)}} - 2 \cot{\left(2 x \right)}\right)
The graph
Derivative of y=ln(ctg2x^3)