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Derivative of (sinx)/(ln(x+2))

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

You have entered [src]
  sin(x)  
----------
log(x + 2)
sin(x)log(x+2)\frac{\sin{\left(x \right)}}{\log{\left(x + 2 \right)}}
sin(x)/log(x + 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)=log(x+2)g{\left(x \right)} = \log{\left(x + 2 \right)}.

    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=x+2u = x + 2.

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

    3. Then, apply the chain rule. Multiply by ddx(x+2)\frac{d}{d x} \left(x + 2\right):

      1. Differentiate x+2x + 2 term by term:

        1. Apply the power rule: xx goes to 11

        2. The derivative of the constant 22 is zero.

        The result is: 11

      The result of the chain rule is:

      1x+2\frac{1}{x + 2}

    Now plug in to the quotient rule:

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

  2. Now simplify:

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


The answer is:

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

The graph
02468-8-6-4-2-1010200-100
The first derivative [src]
  cos(x)            sin(x)      
---------- - -------------------
log(x + 2)              2       
             (x + 2)*log (x + 2)
cos(x)log(x+2)sin(x)(x+2)log(x+2)2\frac{\cos{\left(x \right)}}{\log{\left(x + 2 \right)}} - \frac{\sin{\left(x \right)}}{\left(x + 2\right) \log{\left(x + 2 \right)}^{2}}
The second derivative [src]
                               /        2     \       
                               |1 + ----------|*sin(x)
               2*cos(x)        \    log(2 + x)/       
-sin(x) - ------------------ + -----------------------
          (2 + x)*log(2 + x)            2             
                                 (2 + x) *log(2 + x)  
------------------------------------------------------
                      log(2 + x)                      
(1+2log(x+2))sin(x)(x+2)2log(x+2)sin(x)2cos(x)(x+2)log(x+2)log(x+2)\frac{\frac{\left(1 + \frac{2}{\log{\left(x + 2 \right)}}\right) \sin{\left(x \right)}}{\left(x + 2\right)^{2} \log{\left(x + 2 \right)}} - \sin{\left(x \right)} - \frac{2 \cos{\left(x \right)}}{\left(x + 2\right) \log{\left(x + 2 \right)}}}{\log{\left(x + 2 \right)}}
The third derivative [src]
                                 /        3             3     \                                   
                               2*|1 + ---------- + -----------|*sin(x)     /        2     \       
                                 |    log(2 + x)      2       |          3*|1 + ----------|*cos(x)
               3*sin(x)          \                 log (2 + x)/            \    log(2 + x)/       
-cos(x) + ------------------ - --------------------------------------- + -------------------------
          (2 + x)*log(2 + x)                    3                                  2              
                                         (2 + x) *log(2 + x)                (2 + x) *log(2 + x)   
--------------------------------------------------------------------------------------------------
                                            log(2 + x)                                            
3(1+2log(x+2))cos(x)(x+2)2log(x+2)cos(x)+3sin(x)(x+2)log(x+2)2(1+3log(x+2)+3log(x+2)2)sin(x)(x+2)3log(x+2)log(x+2)\frac{\frac{3 \left(1 + \frac{2}{\log{\left(x + 2 \right)}}\right) \cos{\left(x \right)}}{\left(x + 2\right)^{2} \log{\left(x + 2 \right)}} - \cos{\left(x \right)} + \frac{3 \sin{\left(x \right)}}{\left(x + 2\right) \log{\left(x + 2 \right)}} - \frac{2 \left(1 + \frac{3}{\log{\left(x + 2 \right)}} + \frac{3}{\log{\left(x + 2 \right)}^{2}}\right) \sin{\left(x \right)}}{\left(x + 2\right)^{3} \log{\left(x + 2 \right)}}}{\log{\left(x + 2 \right)}}