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y=sin4^x/cos(8x)

Derivative of y=sin4^x/cos(8x)

Function f() - derivative -N order at the point
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The solution

You have entered [src]
   x    
sin (4) 
--------
cos(8*x)
sinx(4)cos(8x)\frac{\sin^{x}{\left(4 \right)}}{\cos{\left(8 x \right)}}
  /   x    \
d |sin (4) |
--|--------|
dx\cos(8*x)/
ddxsinx(4)cos(8x)\frac{d}{d x} \frac{\sin^{x}{\left(4 \right)}}{\cos{\left(8 x \right)}}
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)=sinx(4)f{\left(x \right)} = \sin^{x}{\left(4 \right)} and g(x)=cos(8x)g{\left(x \right)} = \cos{\left(8 x \right)}.

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

    1. ddxsinx(4)=(log(sin(4))+iπ)sinx(4)\frac{d}{d x} \sin^{x}{\left(4 \right)} = \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) \sin^{x}{\left(4 \right)}

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

    1. Let u=8xu = 8 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 ddx8x\frac{d}{d x} 8 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: 88

      The result of the chain rule is:

      8sin(8x)- 8 \sin{\left(8 x \right)}

    Now plug in to the quotient rule:

    8sinx(4)sin(8x)+(log(sin(4))+iπ)sinx(4)cos(8x)cos2(8x)\frac{8 \sin^{x}{\left(4 \right)} \sin{\left(8 x \right)} + \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) \sin^{x}{\left(4 \right)} \cos{\left(8 x \right)}}{\cos^{2}{\left(8 x \right)}}

  2. Now simplify:

    (8sin(8x)+(log(sin(4))+iπ)cos(8x))sinx(4)cos2(8x)\frac{\left(8 \sin{\left(8 x \right)} + \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) \cos{\left(8 x \right)}\right) \sin^{x}{\left(4 \right)}}{\cos^{2}{\left(8 x \right)}}


The answer is:

(8sin(8x)+(log(sin(4))+iπ)cos(8x))sinx(4)cos2(8x)\frac{\left(8 \sin{\left(8 x \right)} + \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) \cos{\left(8 x \right)}\right) \sin^{x}{\left(4 \right)}}{\cos^{2}{\left(8 x \right)}}

The graph
02468-8-6-4-2-1010-200200
The first derivative [src]
   x                                 x            
sin (4)*(pi*I + log(-sin(4)))   8*sin (4)*sin(8*x)
----------------------------- + ------------------
           cos(8*x)                    2          
                                    cos (8*x)     
8sinx(4)sin(8x)cos2(8x)+(log(sin(4))+iπ)sinx(4)cos(8x)\frac{8 \sin^{x}{\left(4 \right)} \sin{\left(8 x \right)}}{\cos^{2}{\left(8 x \right)}} + \frac{\left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) \sin^{x}{\left(4 \right)}}{\cos{\left(8 x \right)}}
The second derivative [src]
        /                                     2                                         \
   x    |                          2   128*sin (8*x)   16*(pi*I + log(-sin(4)))*sin(8*x)|
sin (4)*|64 + (pi*I + log(-sin(4)))  + ------------- + ---------------------------------|
        |                                   2                       cos(8*x)            |
        \                                cos (8*x)                                      /
-----------------------------------------------------------------------------------------
                                         cos(8*x)                                        
(128sin2(8x)cos2(8x)+16(log(sin(4))+iπ)sin(8x)cos(8x)+64+(log(sin(4))+iπ)2)sinx(4)cos(8x)\frac{\left(\frac{128 \sin^{2}{\left(8 x \right)}}{\cos^{2}{\left(8 x \right)}} + \frac{16 \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) \sin{\left(8 x \right)}}{\cos{\left(8 x \right)}} + 64 + \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right)^{2}\right) \sin^{x}{\left(4 \right)}}{\cos{\left(8 x \right)}}
The third derivative [src]
        /                                                                                                                /         2     \         \
        |                                                                                                                |    6*sin (8*x)|         |
        |                                                                                                            512*|5 + -----------|*sin(8*x)|
        |                             /         2     \                                                 2                |        2      |         |
   x    |                     3       |    2*sin (8*x)|                         24*(pi*I + log(-sin(4))) *sin(8*x)       \     cos (8*x) /         |
sin (4)*|(pi*I + log(-sin(4)))  + 192*|1 + -----------|*(pi*I + log(-sin(4))) + ---------------------------------- + ------------------------------|
        |                             |        2      |                                      cos(8*x)                           cos(8*x)           |
        \                             \     cos (8*x) /                                                                                            /
----------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      cos(8*x)                                                                      
(192(2sin2(8x)cos2(8x)+1)(log(sin(4))+iπ)+512(6sin2(8x)cos2(8x)+5)sin(8x)cos(8x)+24(log(sin(4))+iπ)2sin(8x)cos(8x)+(log(sin(4))+iπ)3)sinx(4)cos(8x)\frac{\left(192 \cdot \left(\frac{2 \sin^{2}{\left(8 x \right)}}{\cos^{2}{\left(8 x \right)}} + 1\right) \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right) + \frac{512 \cdot \left(\frac{6 \sin^{2}{\left(8 x \right)}}{\cos^{2}{\left(8 x \right)}} + 5\right) \sin{\left(8 x \right)}}{\cos{\left(8 x \right)}} + \frac{24 \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right)^{2} \sin{\left(8 x \right)}}{\cos{\left(8 x \right)}} + \left(\log{\left(- \sin{\left(4 \right)} \right)} + i \pi\right)^{3}\right) \sin^{x}{\left(4 \right)}}{\cos{\left(8 x \right)}}
The graph
Derivative of y=sin4^x/cos(8x)