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

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

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The solution

You have entered [src]
 3      
x  - 2*x
--------
 x + 2  
x32xx+2\frac{x^{3} - 2 x}{x + 2}
(x^3 - 2*x)/(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)=x32xf{\left(x \right)} = x^{3} - 2 x and g(x)=x+2g{\left(x \right)} = x + 2.

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

    1. Differentiate x32xx^{3} - 2 x term by term:

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

      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: 2-2

      The result is: 3x223 x^{2} - 2

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

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

      1. The derivative of the constant 22 is zero.

      2. Apply the power rule: xx goes to 11

      The result is: 11

    Now plug in to the quotient rule:

    x3+2x+(x+2)(3x22)(x+2)2\frac{- x^{3} + 2 x + \left(x + 2\right) \left(3 x^{2} - 2\right)}{\left(x + 2\right)^{2}}

  2. Now simplify:

    2(x3+3x22)x2+4x+4\frac{2 \left(x^{3} + 3 x^{2} - 2\right)}{x^{2} + 4 x + 4}


The answer is:

2(x3+3x22)x2+4x+4\frac{2 \left(x^{3} + 3 x^{2} - 2\right)}{x^{2} + 4 x + 4}

The graph
02468-8-6-4-2-1010-5001000
The first derivative [src]
        2    3      
-2 + 3*x    x  - 2*x
--------- - --------
  x + 2            2
            (x + 2) 
3x22x+2x32x(x+2)2\frac{3 x^{2} - 2}{x + 2} - \frac{x^{3} - 2 x}{\left(x + 2\right)^{2}}
The second derivative [src]
  /              2     /      2\\
  |      -2 + 3*x    x*\-2 + x /|
2*|3*x - --------- + -----------|
  |        2 + x              2 |
  \                    (2 + x)  /
---------------------------------
              2 + x              
2(3x+x(x22)(x+2)23x22x+2)x+2\frac{2 \left(3 x + \frac{x \left(x^{2} - 2\right)}{\left(x + 2\right)^{2}} - \frac{3 x^{2} - 2}{x + 2}\right)}{x + 2}
The third derivative [src]
  /            2             /      2\\
  |    -2 + 3*x     3*x    x*\-2 + x /|
6*|1 + --------- - ----- - -----------|
  |            2   2 + x            3 |
  \     (2 + x)              (2 + x)  /
---------------------------------------
                 2 + x                 
6(3xx+2x(x22)(x+2)3+1+3x22(x+2)2)x+2\frac{6 \left(- \frac{3 x}{x + 2} - \frac{x \left(x^{2} - 2\right)}{\left(x + 2\right)^{3}} + 1 + \frac{3 x^{2} - 2}{\left(x + 2\right)^{2}}\right)}{x + 2}