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y=lnctg((x/3)+(pi/4))

Derivative of y=lnctg((x/3)+(pi/4))

Function f() - derivative -N order at the point
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You have entered [src]
   /   /x   pi\\
log|cot|- + --||
   \   \3   4 //
log(cot(x3+π4))\log{\left(\cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)} \right)}
log(cot(x/3 + pi/4))
Detail solution
  1. Let u=cot(x3+π4)u = \cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)}.

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

  3. Then, apply the chain rule. Multiply by ddxcot(x3+π4)\frac{d}{d x} \cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)}:

    1. There are multiple ways to do this derivative.

      Method #1

      1. Rewrite the function to be differentiated:

        cot(x3+π4)=1tan(x3+π4)\cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)} = \frac{1}{\tan{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}

      2. Let u=tan(x3+π4)u = \tan{\left(\frac{x}{3} + \frac{\pi}{4} \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(x3+π4)\frac{d}{d x} \tan{\left(\frac{x}{3} + \frac{\pi}{4} \right)}:

        1. Rewrite the function to be differentiated:

          tan(x3+π4)=sin(x3+π4)cos(x3+π4)\tan{\left(\frac{x}{3} + \frac{\pi}{4} \right)} = \frac{\sin{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{\cos{\left(\frac{x}{3} + \frac{\pi}{4} \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(x3+π4)f{\left(x \right)} = \sin{\left(\frac{x}{3} + \frac{\pi}{4} \right)} and g(x)=cos(x3+π4)g{\left(x \right)} = \cos{\left(\frac{x}{3} + \frac{\pi}{4} \right)}.

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

          1. Let u=x3+π4u = \frac{x}{3} + \frac{\pi}{4}.

          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 ddx(x3+π4)\frac{d}{d x} \left(\frac{x}{3} + \frac{\pi}{4}\right):

            1. Differentiate x3+π4\frac{x}{3} + \frac{\pi}{4} 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: 13\frac{1}{3}

              2. The derivative of the constant π4\frac{\pi}{4} is zero.

              The result is: 13\frac{1}{3}

            The result of the chain rule is:

            cos(x3+π4)3\frac{\cos{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}

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

          1. Let u=x3+π4u = \frac{x}{3} + \frac{\pi}{4}.

          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 ddx(x3+π4)\frac{d}{d x} \left(\frac{x}{3} + \frac{\pi}{4}\right):

            1. Differentiate x3+π4\frac{x}{3} + \frac{\pi}{4} 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: 13\frac{1}{3}

              2. The derivative of the constant π4\frac{\pi}{4} is zero.

              The result is: 13\frac{1}{3}

            The result of the chain rule is:

            sin(x3+π4)3- \frac{\sin{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}

          Now plug in to the quotient rule:

          sin2(x3+π4)3+cos2(x3+π4)3cos2(x3+π4)\frac{\frac{\sin^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3} + \frac{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}}{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}

        The result of the chain rule is:

        sin2(x3+π4)3+cos2(x3+π4)3cos2(x3+π4)tan2(x3+π4)- \frac{\frac{\sin^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3} + \frac{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}}{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)} \tan^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}

      Method #2

      1. Rewrite the function to be differentiated:

        cot(x3+π4)=cos(x3+π4)sin(x3+π4)\cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)} = \frac{\cos{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{\sin{\left(\frac{x}{3} + \frac{\pi}{4} \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(x3+π4)f{\left(x \right)} = \cos{\left(\frac{x}{3} + \frac{\pi}{4} \right)} and g(x)=sin(x3+π4)g{\left(x \right)} = \sin{\left(\frac{x}{3} + \frac{\pi}{4} \right)}.

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

        1. Let u=x3+π4u = \frac{x}{3} + \frac{\pi}{4}.

        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 ddx(x3+π4)\frac{d}{d x} \left(\frac{x}{3} + \frac{\pi}{4}\right):

          1. Differentiate x3+π4\frac{x}{3} + \frac{\pi}{4} 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: 13\frac{1}{3}

            2. The derivative of the constant π4\frac{\pi}{4} is zero.

            The result is: 13\frac{1}{3}

          The result of the chain rule is:

          sin(x3+π4)3- \frac{\sin{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}

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

        1. Let u=x3+π4u = \frac{x}{3} + \frac{\pi}{4}.

        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 ddx(x3+π4)\frac{d}{d x} \left(\frac{x}{3} + \frac{\pi}{4}\right):

          1. Differentiate x3+π4\frac{x}{3} + \frac{\pi}{4} 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: 13\frac{1}{3}

            2. The derivative of the constant π4\frac{\pi}{4} is zero.

            The result is: 13\frac{1}{3}

          The result of the chain rule is:

          cos(x3+π4)3\frac{\cos{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}

        Now plug in to the quotient rule:

        sin2(x3+π4)3cos2(x3+π4)3sin2(x3+π4)\frac{- \frac{\sin^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3} - \frac{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}}{\sin^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}

    The result of the chain rule is:

    sin2(x3+π4)3+cos2(x3+π4)3cos2(x3+π4)tan2(x3+π4)cot(x3+π4)- \frac{\frac{\sin^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3} + \frac{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3}}{\cos^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)} \tan^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)} \cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}

  4. Now simplify:

    23(sin(2x3)1)tan(x3+π4)\frac{2}{3 \left(\sin{\left(\frac{2 x}{3} \right)} - 1\right) \tan{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}


The answer is:

23(sin(2x3)1)tan(x3+π4)\frac{2}{3 \left(\sin{\left(\frac{2 x}{3} \right)} - 1\right) \tan{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}

The graph
02468-8-6-4-2-1010-5050
The first derivative [src]
         2/x   pi\
      cot |- + --|
  1       \3   4 /
- - - ------------
  3        3      
------------------
      /x   pi\    
   cot|- + --|    
      \3   4 /    
cot2(x3+π4)313cot(x3+π4)\frac{- \frac{\cot^{2}{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}{3} - \frac{1}{3}}{\cot{\left(\frac{x}{3} + \frac{\pi}{4} \right)}}
The second derivative [src]
                                               2
                         /       2/3*pi + 4*x\\ 
                         |1 + cot |----------|| 
         2/3*pi + 4*x\   \        \    12    // 
2 + 2*cot |----------| - -----------------------
          \    12    /          2/3*pi + 4*x\   
                             cot |----------|   
                                 \    12    /   
------------------------------------------------
                       9                        
(cot2(4x+3π12)+1)2cot2(4x+3π12)+2cot2(4x+3π12)+29\frac{- \frac{\left(\cot^{2}{\left(\frac{4 x + 3 \pi}{12} \right)} + 1\right)^{2}}{\cot^{2}{\left(\frac{4 x + 3 \pi}{12} \right)}} + 2 \cot^{2}{\left(\frac{4 x + 3 \pi}{12} \right)} + 2}{9}
The third derivative [src]
                         /                                            2                           \
                         |                      /       2/3*pi + 4*x\\      /       2/3*pi + 4*x\\|
                         |                      |1 + cot |----------||    2*|1 + cot |----------|||
  /       2/3*pi + 4*x\\ |       /3*pi + 4*x\   \        \    12    //      \        \    12    //|
2*|1 + cot |----------||*|- 2*cot|----------| - ----------------------- + ------------------------|
  \        \    12    // |       \    12    /          3/3*pi + 4*x\             /3*pi + 4*x\     |
                         |                          cot |----------|          cot|----------|     |
                         \                              \    12    /             \    12    /     /
---------------------------------------------------------------------------------------------------
                                                 27                                                
2(cot2(4x+3π12)+1)((cot2(4x+3π12)+1)2cot3(4x+3π12)+2(cot2(4x+3π12)+1)cot(4x+3π12)2cot(4x+3π12))27\frac{2 \left(\cot^{2}{\left(\frac{4 x + 3 \pi}{12} \right)} + 1\right) \left(- \frac{\left(\cot^{2}{\left(\frac{4 x + 3 \pi}{12} \right)} + 1\right)^{2}}{\cot^{3}{\left(\frac{4 x + 3 \pi}{12} \right)}} + \frac{2 \left(\cot^{2}{\left(\frac{4 x + 3 \pi}{12} \right)} + 1\right)}{\cot{\left(\frac{4 x + 3 \pi}{12} \right)}} - 2 \cot{\left(\frac{4 x + 3 \pi}{12} \right)}\right)}{27}
The graph
Derivative of y=lnctg((x/3)+(pi/4))