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Derivative of sinx*(logx/log7)

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

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The solution

You have entered [src]
       log(x)
sin(x)*------
       log(7)
log(x)log(7)sin(x)\frac{\log{\left(x \right)}}{\log{\left(7 \right)}} \sin{\left(x \right)}
sin(x)*(log(x)/log(7))
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)=log(x)sin(x)f{\left(x \right)} = \log{\left(x \right)} \sin{\left(x \right)} and g(x)=log(7)g{\left(x \right)} = \log{\left(7 \right)}.

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

    1. Apply the product rule:

      ddxf(x)g(x)=f(x)ddxg(x)+g(x)ddxf(x)\frac{d}{d x} f{\left(x \right)} g{\left(x \right)} = f{\left(x \right)} \frac{d}{d x} g{\left(x \right)} + g{\left(x \right)} \frac{d}{d x} f{\left(x \right)}

      f(x)=log(x)f{\left(x \right)} = \log{\left(x \right)}; to find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

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

      g(x)=sin(x)g{\left(x \right)} = \sin{\left(x \right)}; to find ddxg(x)\frac{d}{d x} g{\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)}

      The result is: log(x)cos(x)+sin(x)x\log{\left(x \right)} \cos{\left(x \right)} + \frac{\sin{\left(x \right)}}{x}

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

    1. The derivative of the constant log(7)\log{\left(7 \right)} is zero.

    Now plug in to the quotient rule:

    log(x)cos(x)+sin(x)xlog(7)\frac{\log{\left(x \right)} \cos{\left(x \right)} + \frac{\sin{\left(x \right)}}{x}}{\log{\left(7 \right)}}

  2. Now simplify:

    xlog(x)cos(x)+sin(x)xlog(7)\frac{x \log{\left(x \right)} \cos{\left(x \right)} + \sin{\left(x \right)}}{x \log{\left(7 \right)}}


The answer is:

xlog(x)cos(x)+sin(x)xlog(7)\frac{x \log{\left(x \right)} \cos{\left(x \right)} + \sin{\left(x \right)}}{x \log{\left(7 \right)}}

The graph
02468-8-6-4-2-10102.5-2.5
The first derivative [src]
 sin(x)    cos(x)*log(x)
-------- + -------------
x*log(7)       log(7)   
log(x)cos(x)log(7)+sin(x)xlog(7)\frac{\log{\left(x \right)} \cos{\left(x \right)}}{\log{\left(7 \right)}} + \frac{\sin{\left(x \right)}}{x \log{\left(7 \right)}}
The second derivative [src]
  sin(x)                   2*cos(x)
- ------ - log(x)*sin(x) + --------
     2                        x    
    x                              
-----------------------------------
               log(7)              
log(x)sin(x)+2cos(x)xsin(x)x2log(7)\frac{- \log{\left(x \right)} \sin{\left(x \right)} + \frac{2 \cos{\left(x \right)}}{x} - \frac{\sin{\left(x \right)}}{x^{2}}}{\log{\left(7 \right)}}
The third derivative [src]
                 3*sin(x)   3*cos(x)   2*sin(x)
-cos(x)*log(x) - -------- - -------- + --------
                    x           2          3   
                               x          x    
-----------------------------------------------
                     log(7)                    
log(x)cos(x)3sin(x)x3cos(x)x2+2sin(x)x3log(7)\frac{- \log{\left(x \right)} \cos{\left(x \right)} - \frac{3 \sin{\left(x \right)}}{x} - \frac{3 \cos{\left(x \right)}}{x^{2}} + \frac{2 \sin{\left(x \right)}}{x^{3}}}{\log{\left(7 \right)}}