Mister Exam

Derivative of e^x(sinx-cosx)

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

The graph:

from to

Piecewise:

The solution

You have entered [src]
 x                  
e *(sin(x) - cos(x))
(sin(x)cos(x))ex\left(\sin{\left(x \right)} - \cos{\left(x \right)}\right) e^{x}
d / x                  \
--\e *(sin(x) - cos(x))/
dx                      
ddx(sin(x)cos(x))ex\frac{d}{d x} \left(\sin{\left(x \right)} - \cos{\left(x \right)}\right) e^{x}
Detail solution
  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)=exf{\left(x \right)} = e^{x}; to find ddxf(x)\frac{d}{d x} f{\left(x \right)}:

    1. The derivative of exe^{x} is itself.

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

    1. Differentiate sin(x)cos(x)\sin{\left(x \right)} - \cos{\left(x \right)} term by term:

      1. The derivative of sine is cosine:

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

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

        1. The derivative of cosine is negative sine:

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

        So, the result is: sin(x)\sin{\left(x \right)}

      The result is: sin(x)+cos(x)\sin{\left(x \right)} + \cos{\left(x \right)}

    The result is: (sin(x)cos(x))ex+(sin(x)+cos(x))ex\left(\sin{\left(x \right)} - \cos{\left(x \right)}\right) e^{x} + \left(\sin{\left(x \right)} + \cos{\left(x \right)}\right) e^{x}

  2. Now simplify:

    2exsin(x)2 e^{x} \sin{\left(x \right)}


The answer is:

2exsin(x)2 e^{x} \sin{\left(x \right)}

The graph
02468-8-6-4-2-1010-5000050000
The first derivative [src]
                   x                      x
(cos(x) + sin(x))*e  + (sin(x) - cos(x))*e 
(sin(x)cos(x))ex+(sin(x)+cos(x))ex\left(\sin{\left(x \right)} - \cos{\left(x \right)}\right) e^{x} + \left(\sin{\left(x \right)} + \cos{\left(x \right)}\right) e^{x}
The second derivative [src]
                     x
2*(cos(x) + sin(x))*e 
2(sin(x)+cos(x))ex2 \left(\sin{\left(x \right)} + \cos{\left(x \right)}\right) e^{x}
The third derivative [src]
          x
4*cos(x)*e 
4excos(x)4 e^{x} \cos{\left(x \right)}
The graph
Derivative of e^x(sinx-cosx)