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Derivative of (sin(t)-t*cos(t))/(cos(t)+t*sin(t))

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
sin(t) - t*cos(t)
-----------------
cos(t) + t*sin(t)
$$\frac{- t \cos{\left(t \right)} + \sin{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}}$$
(sin(t) - t*cos(t))/(cos(t) + t*sin(t))
Detail solution
  1. Apply the quotient rule, which is:

    and .

    To find :

    1. Differentiate term by term:

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

        1. Apply the product rule:

          ; to find :

          1. Apply the power rule: goes to

          ; to find :

          1. The derivative of cosine is negative sine:

          The result is:

        So, the result is:

      2. The derivative of sine is cosine:

      The result is:

    To find :

    1. Differentiate term by term:

      1. Apply the product rule:

        ; to find :

        1. Apply the power rule: goes to

        ; to find :

        1. The derivative of sine is cosine:

        The result is:

      2. The derivative of cosine is negative sine:

      The result is:

    Now plug in to the quotient rule:

  2. Now simplify:


The answer is:

The graph
The first derivative [src]
     t*sin(t)       t*(sin(t) - t*cos(t))*cos(t)
----------------- - ----------------------------
cos(t) + t*sin(t)                          2    
                        (cos(t) + t*sin(t))     
$$\frac{t \sin{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} - \frac{t \left(- t \cos{\left(t \right)} + \sin{\left(t \right)}\right) \cos{\left(t \right)}}{\left(t \sin{\left(t \right)} + \cos{\left(t \right)}\right)^{2}}$$
The second derivative [src]
                                /                           2    2     \                              
                                |                        2*t *cos (t)  |                              
           (-sin(t) + t*cos(t))*|-cos(t) + t*sin(t) + -----------------|      2                       
                                \                     t*sin(t) + cos(t)/   2*t *cos(t)*sin(t)         
t*cos(t) - ------------------------------------------------------------- - ------------------ + sin(t)
                                 t*sin(t) + cos(t)                         t*sin(t) + cos(t)          
------------------------------------------------------------------------------------------------------
                                          t*sin(t) + cos(t)                                           
$$\frac{- \frac{2 t^{2} \sin{\left(t \right)} \cos{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + t \cos{\left(t \right)} + \sin{\left(t \right)} - \frac{\left(t \cos{\left(t \right)} - \sin{\left(t \right)}\right) \left(\frac{2 t^{2} \cos^{2}{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + t \sin{\left(t \right)} - \cos{\left(t \right)}\right)}{t \sin{\left(t \right)} + \cos{\left(t \right)}}}{t \sin{\left(t \right)} + \cos{\left(t \right)}}$$
The third derivative [src]
                                           /                             3    3                    2            2              \                                                                                       
                                           |                          6*t *cos (t)          6*t*cos (t)      6*t *cos(t)*sin(t)|                                        /                           2    2     \       
                      (-sin(t) + t*cos(t))*|2*sin(t) + t*cos(t) - -------------------- + ----------------- - ------------------|                                        |                        2*t *cos (t)  |       
                                           |                                         2   t*sin(t) + cos(t)   t*sin(t) + cos(t) |                                    3*t*|-cos(t) + t*sin(t) + -----------------|*sin(t)
                                           \                      (t*sin(t) + cos(t))                                          /   3*t*(t*cos(t) + sin(t))*cos(t)       \                     t*sin(t) + cos(t)/       
2*cos(t) - t*sin(t) - ---------------------------------------------------------------------------------------------------------- - ------------------------------ + ---------------------------------------------------
                                                                  t*sin(t) + cos(t)                                                      t*sin(t) + cos(t)                           t*sin(t) + cos(t)                 
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                   t*sin(t) + cos(t)                                                                                                   
$$\frac{- t \sin{\left(t \right)} - \frac{3 t \left(t \cos{\left(t \right)} + \sin{\left(t \right)}\right) \cos{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + \frac{3 t \left(\frac{2 t^{2} \cos^{2}{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + t \sin{\left(t \right)} - \cos{\left(t \right)}\right) \sin{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + 2 \cos{\left(t \right)} - \frac{\left(t \cos{\left(t \right)} - \sin{\left(t \right)}\right) \left(- \frac{6 t^{3} \cos^{3}{\left(t \right)}}{\left(t \sin{\left(t \right)} + \cos{\left(t \right)}\right)^{2}} - \frac{6 t^{2} \sin{\left(t \right)} \cos{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + t \cos{\left(t \right)} + \frac{6 t \cos^{2}{\left(t \right)}}{t \sin{\left(t \right)} + \cos{\left(t \right)}} + 2 \sin{\left(t \right)}\right)}{t \sin{\left(t \right)} + \cos{\left(t \right)}}}{t \sin{\left(t \right)} + \cos{\left(t \right)}}$$