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Derivative of sqrt(x^(3)-2x)cosx

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
   __________       
  /  3              
\/  x  - 2*x *cos(x)
$$\sqrt{x^{3} - 2 x} \cos{\left(x \right)}$$
sqrt(x^3 - 2*x)*cos(x)
Detail solution
  1. Apply the product rule:

    ; to find :

    1. Let .

    2. Apply the power rule: goes to

    3. Then, apply the chain rule. Multiply by :

      1. Differentiate term by term:

        1. Apply the power rule: goes to

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

          1. Apply the power rule: goes to

          So, the result is:

        The result is:

      The result of the chain rule is:

    ; to find :

    1. The derivative of cosine is negative sine:

    The result is:

  2. Now simplify:


The answer is:

The graph
The first derivative [src]
                         /        2\       
                         |     3*x |       
     __________          |-1 + ----|*cos(x)
    /  3                 \      2  /       
- \/  x  - 2*x *sin(x) + ------------------
                              __________   
                             /  3          
                           \/  x  - 2*x    
$$\frac{\left(\frac{3 x^{2}}{2} - 1\right) \cos{\left(x \right)}}{\sqrt{x^{3} - 2 x}} - \sqrt{x^{3} - 2 x} \sin{\left(x \right)}$$
The second derivative [src]
                                                 /                  2\       
                                                 |       /        2\ |       
                                                 |       \-2 + 3*x / |       
                                                 |12*x - ------------|*cos(x)
     _____________          /        2\          |         /      2\ |       
    /   /      2\           \-2 + 3*x /*sin(x)   \       x*\-2 + x / /       
- \/  x*\-2 + x / *cos(x) - ------------------ + ----------------------------
                                _____________              _____________     
                               /   /      2\              /   /      2\      
                             \/  x*\-2 + x /          4*\/  x*\-2 + x /      
$$- \sqrt{x \left(x^{2} - 2\right)} \cos{\left(x \right)} + \frac{\left(12 x - \frac{\left(3 x^{2} - 2\right)^{2}}{x \left(x^{2} - 2\right)}\right) \cos{\left(x \right)}}{4 \sqrt{x \left(x^{2} - 2\right)}} - \frac{\left(3 x^{2} - 2\right) \sin{\left(x \right)}}{\sqrt{x \left(x^{2} - 2\right)}}$$
The third derivative [src]
                                                                                    /                                 3\       
                                                   /                  2\            |       /        2\    /        2\ |       
                                                   |       /        2\ |            |    12*\-2 + 3*x /    \-2 + 3*x / |       
                                                   |       \-2 + 3*x / |          3*|8 - -------------- + -------------|*cos(x)
                                                 3*|12*x - ------------|*sin(x)     |             2                   2|       
   _____________            /        2\            |         /      2\ |            |       -2 + x         2 /      2\ |       
  /   /      2\           3*\-2 + 3*x /*cos(x)     \       x*\-2 + x / /            \                     x *\-2 + x / /       
\/  x*\-2 + x / *sin(x) - -------------------- - ------------------------------ + ---------------------------------------------
                                _____________               _____________                            _____________             
                               /   /      2\               /   /      2\                            /   /      2\              
                           2*\/  x*\-2 + x /           4*\/  x*\-2 + x /                        8*\/  x*\-2 + x /              
$$\sqrt{x \left(x^{2} - 2\right)} \sin{\left(x \right)} - \frac{3 \left(12 x - \frac{\left(3 x^{2} - 2\right)^{2}}{x \left(x^{2} - 2\right)}\right) \sin{\left(x \right)}}{4 \sqrt{x \left(x^{2} - 2\right)}} - \frac{3 \left(3 x^{2} - 2\right) \cos{\left(x \right)}}{2 \sqrt{x \left(x^{2} - 2\right)}} + \frac{3 \left(8 - \frac{12 \left(3 x^{2} - 2\right)}{x^{2} - 2} + \frac{\left(3 x^{2} - 2\right)^{3}}{x^{2} \left(x^{2} - 2\right)^{2}}\right) \cos{\left(x \right)}}{8 \sqrt{x \left(x^{2} - 2\right)}}$$