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(log(4x-2)/log(3))/ctg(2x)

Derivative of (log(4x-2)/log(3))/ctg(2x)

Function f() - derivative -N order at the point
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  log(4*x - 2) 
---------------
log(3)*cot(2*x)
log(4x2)log(3)cot(2x)\frac{\log{\left(4 x - 2 \right)}}{\log{\left(3 \right)} \cot{\left(2 x \right)}}
d /  log(4*x - 2) \
--|---------------|
dx\log(3)*cot(2*x)/
ddxlog(4x2)log(3)cot(2x)\frac{d}{d x} \frac{\log{\left(4 x - 2 \right)}}{\log{\left(3 \right)} \cot{\left(2 x \right)}}
Detail solution
  1. The derivative of a constant times a function is the constant times the derivative of the function.

    1. 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)=log(4x2)f{\left(x \right)} = \log{\left(4 x - 2 \right)} and g(x)=cot(2x)g{\left(x \right)} = \cot{\left(2 x \right)}.

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

      1. Let u=4x2u = 4 x - 2.

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

      3. Then, apply the chain rule. Multiply by ddx(4x2)\frac{d}{d x} \left(4 x - 2\right):

        1. Differentiate 4x24 x - 2 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: xx goes to 11

            So, the result is: 44

          2. The derivative of the constant (1)2\left(-1\right) 2 is zero.

          The result is: 44

        The result of the chain rule is:

        44x2\frac{4}{4 x - 2}

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

      Now plug in to the quotient rule:

      (2sin2(2x)+2cos2(2x))log(4x2)cos2(2x)tan2(2x)+4cot(2x)4x2cot2(2x)\frac{\frac{\left(2 \sin^{2}{\left(2 x \right)} + 2 \cos^{2}{\left(2 x \right)}\right) \log{\left(4 x - 2 \right)}}{\cos^{2}{\left(2 x \right)} \tan^{2}{\left(2 x \right)}} + \frac{4 \cot{\left(2 x \right)}}{4 x - 2}}{\cot^{2}{\left(2 x \right)}}

    So, the result is: (2sin2(2x)+2cos2(2x))log(4x2)cos2(2x)tan2(2x)+4cot(2x)4x2log(3)cot2(2x)\frac{\frac{\left(2 \sin^{2}{\left(2 x \right)} + 2 \cos^{2}{\left(2 x \right)}\right) \log{\left(4 x - 2 \right)}}{\cos^{2}{\left(2 x \right)} \tan^{2}{\left(2 x \right)}} + \frac{4 \cot{\left(2 x \right)}}{4 x - 2}}{\log{\left(3 \right)} \cot^{2}{\left(2 x \right)}}

  2. Now simplify:

    2((2x1)log(4x2)+sin(4x)2)(2x1)log(3)cos2(2x)\frac{2 \left(\left(2 x - 1\right) \log{\left(4 x - 2 \right)} + \frac{\sin{\left(4 x \right)}}{2}\right)}{\left(2 x - 1\right) \log{\left(3 \right)} \cos^{2}{\left(2 x \right)}}


The answer is:

2((2x1)log(4x2)+sin(4x)2)(2x1)log(3)cos2(2x)\frac{2 \left(\left(2 x - 1\right) \log{\left(4 x - 2 \right)} + \frac{\sin{\left(4 x \right)}}{2}\right)}{\left(2 x - 1\right) \log{\left(3 \right)} \cos^{2}{\left(2 x \right)}}

The graph
02468-8-6-4-2-1010-1000010000
The first derivative [src]
                            /         2     \             
            4               \2 + 2*cot (2*x)/*log(4*x - 2)
------------------------- + ------------------------------
(4*x - 2)*cot(2*x)*log(3)             2                   
                                   cot (2*x)*log(3)       
(2cot2(2x)+2)log(4x2)log(3)cot2(2x)+4(4x2)log(3)cot(2x)\frac{\left(2 \cot^{2}{\left(2 x \right)} + 2\right) \log{\left(4 x - 2 \right)}}{\log{\left(3 \right)} \cot^{2}{\left(2 x \right)}} + \frac{4}{\left(4 x - 2\right) \log{\left(3 \right)} \cot{\left(2 x \right)}}
The second derivative [src]
  /                   /       2     \                      /            2     \                  \
  |       1         2*\1 + cot (2*x)/      /       2     \ |     1 + cot (2*x)|                  |
4*|- ----------- + ------------------- + 2*\1 + cot (2*x)/*|-1 + -------------|*log(2*(-1 + 2*x))|
  |            2   (-1 + 2*x)*cot(2*x)                     |          2       |                  |
  \  (-1 + 2*x)                                            \       cot (2*x)  /                  /
--------------------------------------------------------------------------------------------------
                                         cot(2*x)*log(3)                                          
4(2(1+cot2(2x)+1cot2(2x))(cot2(2x)+1)log(2(2x1))+2(cot2(2x)+1)(2x1)cot(2x)1(2x1)2)log(3)cot(2x)\frac{4 \cdot \left(2 \left(-1 + \frac{\cot^{2}{\left(2 x \right)} + 1}{\cot^{2}{\left(2 x \right)}}\right) \left(\cot^{2}{\left(2 x \right)} + 1\right) \log{\left(2 \cdot \left(2 x - 1\right) \right)} + \frac{2 \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\left(2 x - 1\right) \cot{\left(2 x \right)}} - \frac{1}{\left(2 x - 1\right)^{2}}\right)}{\log{\left(3 \right)} \cot{\left(2 x \right)}}
The third derivative [src]
  /                                                                                                                                                   /            2     \\
  |                                                                                                                                   /       2     \ |     1 + cot (2*x)||
  |                         /                                   2                    3\                                             6*\1 + cot (2*x)/*|-1 + -------------||
  |                         |                    /       2     \      /       2     \ |                         /       2     \                       |          2       ||
  |         2               |         2        5*\1 + cot (2*x)/    3*\1 + cot (2*x)/ |                       3*\1 + cot (2*x)/                       \       cot (2*x)  /|
8*|-------------------- + 2*|2 + 2*cot (2*x) - ------------------ + ------------------|*log(2*(-1 + 2*x)) - --------------------- + --------------------------------------|
  |          3              |                         2                    4          |                               2    2                 (-1 + 2*x)*cot(2*x)          |
  \(-1 + 2*x) *cot(2*x)     \                      cot (2*x)            cot (2*x)     /                     (-1 + 2*x) *cot (2*x)                                         /
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                   log(3)                                                                                  
8(2(2cot2(2x)5(cot2(2x)+1)2cot2(2x)+2+3(cot2(2x)+1)3cot4(2x))log(2(2x1))+6(1+cot2(2x)+1cot2(2x))(cot2(2x)+1)(2x1)cot(2x)3(cot2(2x)+1)(2x1)2cot2(2x)+2(2x1)3cot(2x))log(3)\frac{8 \cdot \left(2 \cdot \left(2 \cot^{2}{\left(2 x \right)} - \frac{5 \left(\cot^{2}{\left(2 x \right)} + 1\right)^{2}}{\cot^{2}{\left(2 x \right)}} + 2 + \frac{3 \left(\cot^{2}{\left(2 x \right)} + 1\right)^{3}}{\cot^{4}{\left(2 x \right)}}\right) \log{\left(2 \cdot \left(2 x - 1\right) \right)} + \frac{6 \left(-1 + \frac{\cot^{2}{\left(2 x \right)} + 1}{\cot^{2}{\left(2 x \right)}}\right) \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\left(2 x - 1\right) \cot{\left(2 x \right)}} - \frac{3 \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\left(2 x - 1\right)^{2} \cot^{2}{\left(2 x \right)}} + \frac{2}{\left(2 x - 1\right)^{3} \cot{\left(2 x \right)}}\right)}{\log{\left(3 \right)}}
The graph
Derivative of (log(4x-2)/log(3))/ctg(2x)