Производная log(x)/log(sin(x))

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Кусочно-заданная:

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Решение

Вы ввели [src]
   log(x)  
-----------
log(sin(x))
log(x)log(sin(x))\frac{\log{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)}}
d /   log(x)  \
--|-----------|
dx\log(sin(x))/
ddxlog(x)log(sin(x))\frac{d}{d x} \frac{\log{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)}}
Подробное решение
  1. Применим правило производной частного:

    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)f{\left(x \right)} = \log{\left(x \right)} и g(x)=log(sin(x))g{\left(x \right)} = \log{\left(\sin{\left(x \right)} \right)}.

    Чтобы найти ddxf(x)\frac{d}{d x} f{\left(x \right)}:

    1. Производная log(x)\log{\left(x \right)} является 1x\frac{1}{x}.

    Чтобы найти ddxg(x)\frac{d}{d x} g{\left(x \right)}:

    1. Заменим u=sin(x)u = \sin{\left(x \right)}.

    2. Производная log(u)\log{\left(u \right)} является 1u\frac{1}{u}.

    3. Затем примените цепочку правил. Умножим на ddxsin(x)\frac{d}{d x} \sin{\left(x \right)}:

      1. Производная синуса есть косинус:

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

      В результате последовательности правил:

      cos(x)sin(x)\frac{\cos{\left(x \right)}}{\sin{\left(x \right)}}

    Теперь применим правило производной деления:

    log(x)cos(x)sin(x)+log(sin(x))xlog(sin(x))2\frac{- \frac{\log{\left(x \right)} \cos{\left(x \right)}}{\sin{\left(x \right)}} + \frac{\log{\left(\sin{\left(x \right)} \right)}}{x}}{\log{\left(\sin{\left(x \right)} \right)}^{2}}

  2. Теперь упростим:

    xlog(x)log(sin(x))tan(x)+1xlog(sin(x))\frac{- \frac{x \log{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)} \tan{\left(x \right)}} + 1}{x \log{\left(\sin{\left(x \right)} \right)}}


Ответ:

xlog(x)log(sin(x))tan(x)+1xlog(sin(x))\frac{- \frac{x \log{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)} \tan{\left(x \right)}} + 1}{x \log{\left(\sin{\left(x \right)} \right)}}

График
02468-8-6-4-2-1010-2500025000
Первая производная [src]
      1            cos(x)*log(x)   
------------- - -------------------
x*log(sin(x))      2               
                log (sin(x))*sin(x)
log(x)cos(x)log(sin(x))2sin(x)+1xlog(sin(x))- \frac{\log{\left(x \right)} \cos{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)}^{2} \sin{\left(x \right)}} + \frac{1}{x \log{\left(\sin{\left(x \right)} \right)}}
Вторая производная [src]
       /       2                2        \                              
       |    cos (x)        2*cos (x)     |                              
       |1 + ------- + -------------------|*log(x)                       
       |       2                     2   |                              
  1    \    sin (x)   log(sin(x))*sin (x)/                2*cos(x)      
- -- + ------------------------------------------ - --------------------
   2                  log(sin(x))                   x*log(sin(x))*sin(x)
  x                                                                     
------------------------------------------------------------------------
                              log(sin(x))                               
(1+cos2(x)sin2(x)+2cos2(x)log(sin(x))sin2(x))log(x)log(sin(x))2cos(x)xlog(sin(x))sin(x)1x2log(sin(x))\frac{\frac{\left(1 + \frac{\cos^{2}{\left(x \right)}}{\sin^{2}{\left(x \right)}} + \frac{2 \cos^{2}{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)}}\right) \log{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)}} - \frac{2 \cos{\left(x \right)}}{x \log{\left(\sin{\left(x \right)} \right)} \sin{\left(x \right)}} - \frac{1}{x^{2}}}{\log{\left(\sin{\left(x \right)} \right)}}
Третья производная [src]
       /       2                2        \                             /                     2                2                     2         \              
       |    cos (x)        2*cos (x)     |                             |         3        cos (x)        3*cos (x)             3*cos (x)      |              
     3*|1 + ------- + -------------------|                           2*|1 + ----------- + ------- + ------------------- + --------------------|*cos(x)*log(x)
       |       2                     2   |                             |    log(sin(x))      2                     2         2            2   |              
2      \    sin (x)   log(sin(x))*sin (x)/          3*cos(x)           \                  sin (x)   log(sin(x))*sin (x)   log (sin(x))*sin (x)/              
-- + ------------------------------------- + --------------------- - ----------------------------------------------------------------------------------------
 3               x*log(sin(x))                2                                                         log(sin(x))*sin(x)                                   
x                                            x *log(sin(x))*sin(x)                                                                                           
-------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         log(sin(x))                                                                         
2(1+cos2(x)sin2(x)+3log(sin(x))+3cos2(x)log(sin(x))sin2(x)+3cos2(x)log(sin(x))2sin2(x))log(x)cos(x)log(sin(x))sin(x)+3(1+cos2(x)sin2(x)+2cos2(x)log(sin(x))sin2(x))xlog(sin(x))+3cos(x)x2log(sin(x))sin(x)+2x3log(sin(x))\frac{- \frac{2 \cdot \left(1 + \frac{\cos^{2}{\left(x \right)}}{\sin^{2}{\left(x \right)}} + \frac{3}{\log{\left(\sin{\left(x \right)} \right)}} + \frac{3 \cos^{2}{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)}} + \frac{3 \cos^{2}{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)}^{2} \sin^{2}{\left(x \right)}}\right) \log{\left(x \right)} \cos{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)} \sin{\left(x \right)}} + \frac{3 \cdot \left(1 + \frac{\cos^{2}{\left(x \right)}}{\sin^{2}{\left(x \right)}} + \frac{2 \cos^{2}{\left(x \right)}}{\log{\left(\sin{\left(x \right)} \right)} \sin^{2}{\left(x \right)}}\right)}{x \log{\left(\sin{\left(x \right)} \right)}} + \frac{3 \cos{\left(x \right)}}{x^{2} \log{\left(\sin{\left(x \right)} \right)} \sin{\left(x \right)}} + \frac{2}{x^{3}}}{\log{\left(\sin{\left(x \right)} \right)}}
График
Производная log(x)/log(sin(x)) /media/krcore-image-pods/hash/derivative/e/0f/d29e3f751e3bb56e5c2ff4a04cbea.png