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Derivative of 4-(4-lnx)/x

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

You have entered [src]
    4 - log(x)
4 - ----------
        x     
44log(x)x4 - \frac{4 - \log{\left(x \right)}}{x}
4 - (4 - log(x))/x
Detail solution
  1. Differentiate 44log(x)x4 - \frac{4 - \log{\left(x \right)}}{x} term by term:

    1. The derivative of the constant 44 is zero.

    2. The derivative of a constant times a function is the constant times the derivative of the function.

      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)=4log(x)f{\left(x \right)} = 4 - \log{\left(x \right)} and g(x)=xg{\left(x \right)} = x.

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

        1. Differentiate 4log(x)4 - \log{\left(x \right)} term by term:

          1. The derivative of the constant 44 is zero.

          2. The derivative of a constant times a function is the constant times the derivative of the function.

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

            So, the result is: 1x- \frac{1}{x}

          The result is: 1x- \frac{1}{x}

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

        1. Apply the power rule: xx goes to 11

        Now plug in to the quotient rule:

        log(x)5x2\frac{\log{\left(x \right)} - 5}{x^{2}}

      So, the result is: log(x)5x2- \frac{\log{\left(x \right)} - 5}{x^{2}}

    The result is: log(x)5x2- \frac{\log{\left(x \right)} - 5}{x^{2}}

  2. Now simplify:

    5log(x)x2\frac{5 - \log{\left(x \right)}}{x^{2}}


The answer is:

5log(x)x2\frac{5 - \log{\left(x \right)}}{x^{2}}

The graph
02468-8-6-4-2-1010-10001000
The first derivative [src]
1    -4 + log(x)
-- - -----------
 2         2    
x         x     
log(x)4x2+1x2- \frac{\log{\left(x \right)} - 4}{x^{2}} + \frac{1}{x^{2}}
The second derivative [src]
-11 + 2*log(x)
--------------
       3      
      x       
2log(x)11x3\frac{2 \log{\left(x \right)} - 11}{x^{3}}
The third derivative [src]
35 - 6*log(x)
-------------
       4     
      x      
356log(x)x4\frac{35 - 6 \log{\left(x \right)}}{x^{4}}