Mister Exam

Other calculators


2sin^3x*cosx

Integral of 2sin^3x*cosx dx

Limits of integration:

from to
v

The graph:

from to

Piecewise:

The solution

You have entered [src]
  1                    
  /                    
 |                     
 |       3             
 |  2*sin (x)*cos(x) dx
 |                     
/                      
0                      
012sin3(x)cos(x)dx\int\limits_{0}^{1} 2 \sin^{3}{\left(x \right)} \cos{\left(x \right)}\, dx
Integral(2*sin(x)^3*cos(x), (x, 0, 1))
Detail solution
  1. The integral of a constant times a function is the constant times the integral of the function:

    2sin3(x)cos(x)dx=2sin3(x)cos(x)dx\int 2 \sin^{3}{\left(x \right)} \cos{\left(x \right)}\, dx = 2 \int \sin^{3}{\left(x \right)} \cos{\left(x \right)}\, dx

    1. There are multiple ways to do this integral.

      Method #1

      1. Let u=sin(x)u = \sin{\left(x \right)}.

        Then let du=cos(x)dxdu = \cos{\left(x \right)} dx and substitute dudu:

        u3du\int u^{3}\, du

        1. The integral of unu^{n} is un+1n+1\frac{u^{n + 1}}{n + 1} when n1n \neq -1:

          u3du=u44\int u^{3}\, du = \frac{u^{4}}{4}

        Now substitute uu back in:

        sin4(x)4\frac{\sin^{4}{\left(x \right)}}{4}

      Method #2

      1. Rewrite the integrand:

        sin3(x)cos(x)=(1cos2(x))sin(x)cos(x)\sin^{3}{\left(x \right)} \cos{\left(x \right)} = \left(1 - \cos^{2}{\left(x \right)}\right) \sin{\left(x \right)} \cos{\left(x \right)}

      2. Let u=cos2(x)u = - \cos^{2}{\left(x \right)}.

        Then let du=2sin(x)cos(x)dxdu = 2 \sin{\left(x \right)} \cos{\left(x \right)} dx and substitute dudu:

        (u2+12)du\int \left(\frac{u}{2} + \frac{1}{2}\right)\, du

        1. Integrate term-by-term:

          1. The integral of a constant times a function is the constant times the integral of the function:

            u2du=udu2\int \frac{u}{2}\, du = \frac{\int u\, du}{2}

            1. The integral of unu^{n} is un+1n+1\frac{u^{n + 1}}{n + 1} when n1n \neq -1:

              udu=u22\int u\, du = \frac{u^{2}}{2}

            So, the result is: u24\frac{u^{2}}{4}

          1. The integral of a constant is the constant times the variable of integration:

            12du=u2\int \frac{1}{2}\, du = \frac{u}{2}

          The result is: u24+u2\frac{u^{2}}{4} + \frac{u}{2}

        Now substitute uu back in:

        cos4(x)4cos2(x)2\frac{\cos^{4}{\left(x \right)}}{4} - \frac{\cos^{2}{\left(x \right)}}{2}

    So, the result is: sin4(x)2\frac{\sin^{4}{\left(x \right)}}{2}

  2. Add the constant of integration:

    sin4(x)2+constant\frac{\sin^{4}{\left(x \right)}}{2}+ \mathrm{constant}


The answer is:

sin4(x)2+constant\frac{\sin^{4}{\left(x \right)}}{2}+ \mathrm{constant}

The answer (Indefinite) [src]
  /                                 
 |                              4   
 |      3                    sin (x)
 | 2*sin (x)*cos(x) dx = C + -------
 |                              2   
/                                   
2sin3(x)cos(x)dx=C+sin4(x)2\int 2 \sin^{3}{\left(x \right)} \cos{\left(x \right)}\, dx = C + \frac{\sin^{4}{\left(x \right)}}{2}
The graph
0.001.000.100.200.300.400.500.600.700.800.900.01.0
The answer [src]
   4   
sin (1)
-------
   2   
sin4(1)2\frac{\sin^{4}{\left(1 \right)}}{2}
=
=
   4   
sin (1)
-------
   2   
sin4(1)2\frac{\sin^{4}{\left(1 \right)}}{2}
Numerical answer [src]
0.25068398283281
0.25068398283281
The graph
Integral of 2sin^3x*cosx dx

    Use the examples entering the upper and lower limits of integration.