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y=sinx/(1+cosx)²

Derivative of y=sinx/(1+cosx)²

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

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The solution

You have entered [src]
    sin(x)   
-------------
            2
(1 + cos(x)) 
sin(x)(cos(x)+1)2\frac{\sin{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{2}}
d /    sin(x)   \
--|-------------|
dx|            2|
  \(1 + cos(x)) /
ddxsin(x)(cos(x)+1)2\frac{d}{d x} \frac{\sin{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{2}}
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)=sin(x)f{\left(x \right)} = \sin{\left(x \right)} and g(x)=(cos(x)+1)2g{\left(x \right)} = \left(\cos{\left(x \right)} + 1\right)^{2}.

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

    1. The derivative of sine is cosine:

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

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

    1. Let u=cos(x)+1u = \cos{\left(x \right)} + 1.

    2. Apply the power rule: u2u^{2} goes to 2u2 u

    3. Then, apply the chain rule. Multiply by ddx(cos(x)+1)\frac{d}{d x} \left(\cos{\left(x \right)} + 1\right):

      1. Differentiate cos(x)+1\cos{\left(x \right)} + 1 term by term:

        1. The derivative of the constant 11 is zero.

        2. The derivative of cosine is negative sine:

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

        The result is: sin(x)- \sin{\left(x \right)}

      The result of the chain rule is:

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

    Now plug in to the quotient rule:

    (cos(x)+1)2cos(x)+(2cos(x)+2)sin2(x)(cos(x)+1)4\frac{\left(\cos{\left(x \right)} + 1\right)^{2} \cos{\left(x \right)} + \left(2 \cos{\left(x \right)} + 2\right) \sin^{2}{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{4}}

  2. Now simplify:

    sin2(x)+cos(x)+1(cos(x)+1)3\frac{\sin^{2}{\left(x \right)} + \cos{\left(x \right)} + 1}{\left(\cos{\left(x \right)} + 1\right)^{3}}


The answer is:

sin2(x)+cos(x)+1(cos(x)+1)3\frac{\sin^{2}{\left(x \right)} + \cos{\left(x \right)} + 1}{\left(\cos{\left(x \right)} + 1\right)^{3}}

The graph
02468-8-6-4-2-10102000000000-1000000000
The first derivative [src]
                       2     
    cos(x)        2*sin (x)  
------------- + -------------
            2               3
(1 + cos(x))    (1 + cos(x)) 
cos(x)(cos(x)+1)2+2sin2(x)(cos(x)+1)3\frac{\cos{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{2}} + \frac{2 \sin^{2}{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{3}}
The second derivative [src]
/       /     2             \             \       
|       |3*sin (x)          |             |       
|     2*|---------- + cos(x)|             |       
|       \1 + cos(x)         /    4*cos(x) |       
|-1 + ----------------------- + ----------|*sin(x)
\            1 + cos(x)         1 + cos(x)/       
--------------------------------------------------
                              2                   
                  (1 + cos(x))                    
(1+2(cos(x)+3sin2(x)cos(x)+1)cos(x)+1+4cos(x)cos(x)+1)sin(x)(cos(x)+1)2\frac{\left(-1 + \frac{2 \left(\cos{\left(x \right)} + \frac{3 \sin^{2}{\left(x \right)}}{\cos{\left(x \right)} + 1}\right)}{\cos{\left(x \right)} + 1} + \frac{4 \cos{\left(x \right)}}{\cos{\left(x \right)} + 1}\right) \sin{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{2}}
The third derivative [src]
                                 /                          2    \                                 
                            2    |      9*cos(x)      12*sin (x) |     /     2             \       
                       2*sin (x)*|-1 + ---------- + -------------|     |3*sin (x)          |       
               2                 |     1 + cos(x)               2|   6*|---------- + cos(x)|*cos(x)
          6*sin (x)              \                  (1 + cos(x)) /     \1 + cos(x)         /       
-cos(x) - ---------- + ------------------------------------------- + ------------------------------
          1 + cos(x)                    1 + cos(x)                             1 + cos(x)          
---------------------------------------------------------------------------------------------------
                                                       2                                           
                                           (1 + cos(x))                                            
2(1+9cos(x)cos(x)+1+12sin2(x)(cos(x)+1)2)sin2(x)cos(x)+1cos(x)+6(cos(x)+3sin2(x)cos(x)+1)cos(x)cos(x)+16sin2(x)cos(x)+1(cos(x)+1)2\frac{\frac{2 \left(-1 + \frac{9 \cos{\left(x \right)}}{\cos{\left(x \right)} + 1} + \frac{12 \sin^{2}{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right)^{2}}\right) \sin^{2}{\left(x \right)}}{\cos{\left(x \right)} + 1} - \cos{\left(x \right)} + \frac{6 \left(\cos{\left(x \right)} + \frac{3 \sin^{2}{\left(x \right)}}{\cos{\left(x \right)} + 1}\right) \cos{\left(x \right)}}{\cos{\left(x \right)} + 1} - \frac{6 \sin^{2}{\left(x \right)}}{\cos{\left(x \right)} + 1}}{\left(\cos{\left(x \right)} + 1\right)^{2}}
The graph
Derivative of y=sinx/(1+cosx)²