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x^3/(2*x+4)

Derivative of x^3/(2*x+4)

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

You have entered [src]
    3  
   x   
-------
2*x + 4
x32x+4\frac{x^{3}}{2 x + 4}
x^3/(2*x + 4)
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)=x3f{\left(x \right)} = x^{3} and g(x)=2x+4g{\left(x \right)} = 2 x + 4.

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

    1. Apply the power rule: x3x^{3} goes to 3x23 x^{2}

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

    1. Differentiate 2x+42 x + 4 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 power rule: xx goes to 11

        So, the result is: 22

      The result is: 22

    Now plug in to the quotient rule:

    2x3+3x2(2x+4)(2x+4)2\frac{- 2 x^{3} + 3 x^{2} \left(2 x + 4\right)}{\left(2 x + 4\right)^{2}}

  2. Now simplify:

    x2(x+3)(x+2)2\frac{x^{2} \left(x + 3\right)}{\left(x + 2\right)^{2}}


The answer is:

x2(x+3)(x+2)2\frac{x^{2} \left(x + 3\right)}{\left(x + 2\right)^{2}}

The graph
02468-8-6-4-2-1010-5001000
The first derivative [src]
        3           2 
     2*x         3*x  
- ---------- + -------
           2   2*x + 4
  (2*x + 4)           
2x3(2x+4)2+3x22x+4- \frac{2 x^{3}}{\left(2 x + 4\right)^{2}} + \frac{3 x^{2}}{2 x + 4}
The second derivative [src]
  /        2           \
  |       x        3*x |
x*|3 + -------- - -----|
  |           2   2 + x|
  \    (2 + x)         /
------------------------
         2 + x          
x(x2(x+2)23xx+2+3)x+2\frac{x \left(\frac{x^{2}}{\left(x + 2\right)^{2}} - \frac{3 x}{x + 2} + 3\right)}{x + 2}
The third derivative [src]
  /        3                   2  \
  |       x        3*x      3*x   |
3*|1 - -------- - ----- + --------|
  |           3   2 + x          2|
  \    (2 + x)            (2 + x) /
-----------------------------------
               2 + x               
3(x3(x+2)3+3x2(x+2)23xx+2+1)x+2\frac{3 \left(- \frac{x^{3}}{\left(x + 2\right)^{3}} + \frac{3 x^{2}}{\left(x + 2\right)^{2}} - \frac{3 x}{x + 2} + 1\right)}{x + 2}
The graph
Derivative of x^3/(2*x+4)