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20/3*sin(x)*cos(x)

Derivative of 20/3*sin(x)*cos(x)

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

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The solution

You have entered [src]
20*sin(x)*cos(x)
----------------
       3        
20sin(x)cos(x)3\frac{20 \sin{\left(x \right)} \cos{\left(x \right)}}{3}
d /20*sin(x)*cos(x)\
--|----------------|
dx\       3        /
ddx20sin(x)cos(x)3\frac{d}{d x} \frac{20 \sin{\left(x \right)} \cos{\left(x \right)}}{3}
Detail solution
  1. The derivative of a constant times a function is the constant times the derivative of the function.

    1. Apply the product rule:

      ddxf(x)g(x)=f(x)ddxg(x)+g(x)ddxf(x)\frac{d}{d x} f{\left(x \right)} g{\left(x \right)} = f{\left(x \right)} \frac{d}{d x} g{\left(x \right)} + g{\left(x \right)} \frac{d}{d x} f{\left(x \right)}

      f(x)=cos(x)f{\left(x \right)} = \cos{\left(x \right)}; to find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

      1. The derivative of cosine is negative sine:

        ddxcos(x)=sin(x)\frac{d}{d x} \cos{\left(x \right)} = - \sin{\left(x \right)}

      g(x)=sin(x)g{\left(x \right)} = \sin{\left(x \right)}; to find ddxg(x)\frac{d}{d x} g{\left(x \right)}:

      1. The derivative of sine is cosine:

        ddxsin(x)=cos(x)\frac{d}{d x} \sin{\left(x \right)} = \cos{\left(x \right)}

      The result is: sin2(x)+cos2(x)- \sin^{2}{\left(x \right)} + \cos^{2}{\left(x \right)}

    So, the result is: 20sin2(x)3+20cos2(x)3- \frac{20 \sin^{2}{\left(x \right)}}{3} + \frac{20 \cos^{2}{\left(x \right)}}{3}

  2. Now simplify:

    20cos(2x)3\frac{20 \cos{\left(2 x \right)}}{3}


The answer is:

20cos(2x)3\frac{20 \cos{\left(2 x \right)}}{3}

The graph
02468-8-6-4-2-1010-1010
The first derivative [src]
        2            2   
  20*sin (x)   20*cos (x)
- ---------- + ----------
      3            3     
20sin2(x)3+20cos2(x)3- \frac{20 \sin^{2}{\left(x \right)}}{3} + \frac{20 \cos^{2}{\left(x \right)}}{3}
The second derivative [src]
-80*cos(x)*sin(x)
-----------------
        3        
80sin(x)cos(x)3- \frac{80 \sin{\left(x \right)} \cos{\left(x \right)}}{3}
The third derivative [src]
   /   2         2   \
80*\sin (x) - cos (x)/
----------------------
          3           
80(sin2(x)cos2(x))3\frac{80 \left(\sin^{2}{\left(x \right)} - \cos^{2}{\left(x \right)}\right)}{3}
The graph
Derivative of 20/3*sin(x)*cos(x)