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(sin(x)+x^2)/cot(2*x)

Derivative of (sin(x)+x^2)/cot(2*x)

Function f() - derivative -N order at the point
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          2
sin(x) + x 
-----------
  cot(2*x) 
x2+sin(x)cot(2x)\frac{x^{2} + \sin{\left(x \right)}}{\cot{\left(2 x \right)}}
(sin(x) + x^2)/cot(2*x)
Detail solution
  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)=x2+sin(x)f{\left(x \right)} = x^{2} + \sin{\left(x \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. Differentiate x2+sin(x)x^{2} + \sin{\left(x \right)} term by term:

      1. Apply the power rule: x2x^{2} goes to 2x2 x

      2. The derivative of sine is cosine:

        ddxsin(x)=cos(x)\frac{d}{d x} \sin{\left(x \right)} = \cos{\left(x \right)}

      The result is: 2x+cos(x)2 x + \cos{\left(x \right)}

    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:

    (2x+cos(x))cot(2x)+(x2+sin(x))(2sin2(2x)+2cos2(2x))cos2(2x)tan2(2x)cot2(2x)\frac{\left(2 x + \cos{\left(x \right)}\right) \cot{\left(2 x \right)} + \frac{\left(x^{2} + \sin{\left(x \right)}\right) \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^{2}{\left(2 x \right)}}

  2. Now simplify:

    2x2+(2x+cos(x))sin(2x)cos(2x)+2sin(x)cos2(2x)\frac{2 x^{2} + \left(2 x + \cos{\left(x \right)}\right) \sin{\left(2 x \right)} \cos{\left(2 x \right)} + 2 \sin{\left(x \right)}}{\cos^{2}{\left(2 x \right)}}


The answer is:

2x2+(2x+cos(x))sin(2x)cos(2x)+2sin(x)cos2(2x)\frac{2 x^{2} + \left(2 x + \cos{\left(x \right)}\right) \sin{\left(2 x \right)} \cos{\left(2 x \right)} + 2 \sin{\left(x \right)}}{\cos^{2}{\left(2 x \right)}}

The graph
02468-8-6-4-2-1010-50000100000
The first derivative [src]
               /         2     \ /          2\
2*x + cos(x)   \2 + 2*cot (2*x)/*\sin(x) + x /
------------ + -------------------------------
  cot(2*x)                   2                
                          cot (2*x)           
2x+cos(x)cot(2x)+(x2+sin(x))(2cot2(2x)+2)cot2(2x)\frac{2 x + \cos{\left(x \right)}}{\cot{\left(2 x \right)}} + \frac{\left(x^{2} + \sin{\left(x \right)}\right) \left(2 \cot^{2}{\left(2 x \right)} + 2\right)}{\cot^{2}{\left(2 x \right)}}
The second derivative [src]
               /       2     \                                    /            2     \              
             4*\1 + cot (2*x)/*(2*x + cos(x))     /       2     \ |     1 + cot (2*x)| / 2         \
2 - sin(x) + -------------------------------- + 8*\1 + cot (2*x)/*|-1 + -------------|*\x  + sin(x)/
                         cot(2*x)                                 |          2       |              
                                                                  \       cot (2*x)  /              
----------------------------------------------------------------------------------------------------
                                              cot(2*x)                                              
4(2x+cos(x))(cot2(2x)+1)cot(2x)+8(x2+sin(x))(cot2(2x)+1cot2(2x)1)(cot2(2x)+1)sin(x)+2cot(2x)\frac{\frac{4 \left(2 x + \cos{\left(x \right)}\right) \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\cot{\left(2 x \right)}} + 8 \left(x^{2} + \sin{\left(x \right)}\right) \left(\frac{\cot^{2}{\left(2 x \right)} + 1}{\cot^{2}{\left(2 x \right)}} - 1\right) \left(\cot^{2}{\left(2 x \right)} + 1\right) - \sin{\left(x \right)} + 2}{\cot{\left(2 x \right)}}
The third derivative [src]
                                                                                                                                                 /            2     \               
                                                                                                                                 /       2     \ |     1 + cot (2*x)|               
                              /                                   2                    3\                                     24*\1 + cot (2*x)/*|-1 + -------------|*(2*x + cos(x))
                              |                    /       2     \      /       2     \ |     /       2     \                                    |          2       |               
   cos(x)       / 2         \ |         2        5*\1 + cot (2*x)/    3*\1 + cot (2*x)/ |   6*\1 + cot (2*x)/*(-2 + sin(x))                      \       cot (2*x)  /               
- -------- + 16*\x  + sin(x)/*|2 + 2*cot (2*x) - ------------------ + ------------------| - ------------------------------- + ------------------------------------------------------
  cot(2*x)                    |                         2                    4          |                 2                                          cot(2*x)                       
                              \                      cot (2*x)            cot (2*x)     /              cot (2*x)                                                                    
24(2x+cos(x))(cot2(2x)+1cot2(2x)1)(cot2(2x)+1)cot(2x)+16(x2+sin(x))(3(cot2(2x)+1)3cot4(2x)5(cot2(2x)+1)2cot2(2x)+2cot2(2x)+2)6(sin(x)2)(cot2(2x)+1)cot2(2x)cos(x)cot(2x)\frac{24 \left(2 x + \cos{\left(x \right)}\right) \left(\frac{\cot^{2}{\left(2 x \right)} + 1}{\cot^{2}{\left(2 x \right)}} - 1\right) \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\cot{\left(2 x \right)}} + 16 \left(x^{2} + \sin{\left(x \right)}\right) \left(\frac{3 \left(\cot^{2}{\left(2 x \right)} + 1\right)^{3}}{\cot^{4}{\left(2 x \right)}} - \frac{5 \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) - \frac{6 \left(\sin{\left(x \right)} - 2\right) \left(\cot^{2}{\left(2 x \right)} + 1\right)}{\cot^{2}{\left(2 x \right)}} - \frac{\cos{\left(x \right)}}{\cot{\left(2 x \right)}}
The graph
Derivative of (sin(x)+x^2)/cot(2*x)