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(x^2+4x-2)sin3xdx

Integral of (x^2+4x-2)sin3xdx dx

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01((x2+4x)2)sin(3x)dx\int\limits_{0}^{1} \left(\left(x^{2} + 4 x\right) - 2\right) \sin{\left(3 x \right)}\, dx
Integral((x^2 + 4*x - 2)*sin(3*x), (x, 0, 1))
Detail solution
  1. There are multiple ways to do this integral.

    Method #1

    1. Rewrite the integrand:

      ((x2+4x)2)sin(3x)=x2sin(3x)+4xsin(3x)2sin(3x)\left(\left(x^{2} + 4 x\right) - 2\right) \sin{\left(3 x \right)} = x^{2} \sin{\left(3 x \right)} + 4 x \sin{\left(3 x \right)} - 2 \sin{\left(3 x \right)}

    2. Integrate term-by-term:

      1. Use integration by parts:

        udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

        Let u(x)=x2u{\left(x \right)} = x^{2} and let dv(x)=sin(3x)\operatorname{dv}{\left(x \right)} = \sin{\left(3 x \right)}.

        Then du(x)=2x\operatorname{du}{\left(x \right)} = 2 x.

        To find v(x)v{\left(x \right)}:

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

            sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

            1. The integral of sine is negative cosine:

              sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

            So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

          Now substitute uu back in:

          cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

        Now evaluate the sub-integral.

      2. Use integration by parts:

        udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

        Let u(x)=2x3u{\left(x \right)} = - \frac{2 x}{3} and let dv(x)=cos(3x)\operatorname{dv}{\left(x \right)} = \cos{\left(3 x \right)}.

        Then du(x)=23\operatorname{du}{\left(x \right)} = - \frac{2}{3}.

        To find v(x)v{\left(x \right)}:

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          cos(u)3du\int \frac{\cos{\left(u \right)}}{3}\, du

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

            cos(u)du=cos(u)du3\int \cos{\left(u \right)}\, du = \frac{\int \cos{\left(u \right)}\, du}{3}

            1. The integral of cosine is sine:

              cos(u)du=sin(u)\int \cos{\left(u \right)}\, du = \sin{\left(u \right)}

            So, the result is: sin(u)3\frac{\sin{\left(u \right)}}{3}

          Now substitute uu back in:

          sin(3x)3\frac{\sin{\left(3 x \right)}}{3}

        Now evaluate the sub-integral.

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

        (2sin(3x)9)dx=2sin(3x)dx9\int \left(- \frac{2 \sin{\left(3 x \right)}}{9}\right)\, dx = - \frac{2 \int \sin{\left(3 x \right)}\, dx}{9}

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

            sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

            1. The integral of sine is negative cosine:

              sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

            So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

          Now substitute uu back in:

          cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

        So, the result is: 2cos(3x)27\frac{2 \cos{\left(3 x \right)}}{27}

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

        4xsin(3x)dx=4xsin(3x)dx\int 4 x \sin{\left(3 x \right)}\, dx = 4 \int x \sin{\left(3 x \right)}\, dx

        1. Use integration by parts:

          udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

          Let u(x)=xu{\left(x \right)} = x and let dv(x)=sin(3x)\operatorname{dv}{\left(x \right)} = \sin{\left(3 x \right)}.

          Then du(x)=1\operatorname{du}{\left(x \right)} = 1.

          To find v(x)v{\left(x \right)}:

          1. Let u=3xu = 3 x.

            Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

            sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

              sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

              1. The integral of sine is negative cosine:

                sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

              So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

            Now substitute uu back in:

            cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

          Now evaluate the sub-integral.

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

          (cos(3x)3)dx=cos(3x)dx3\int \left(- \frac{\cos{\left(3 x \right)}}{3}\right)\, dx = - \frac{\int \cos{\left(3 x \right)}\, dx}{3}

          1. Let u=3xu = 3 x.

            Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

            cos(u)3du\int \frac{\cos{\left(u \right)}}{3}\, du

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

              cos(u)du=cos(u)du3\int \cos{\left(u \right)}\, du = \frac{\int \cos{\left(u \right)}\, du}{3}

              1. The integral of cosine is sine:

                cos(u)du=sin(u)\int \cos{\left(u \right)}\, du = \sin{\left(u \right)}

              So, the result is: sin(u)3\frac{\sin{\left(u \right)}}{3}

            Now substitute uu back in:

            sin(3x)3\frac{\sin{\left(3 x \right)}}{3}

          So, the result is: sin(3x)9- \frac{\sin{\left(3 x \right)}}{9}

        So, the result is: 4xcos(3x)3+4sin(3x)9- \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9}

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

        (2sin(3x))dx=2sin(3x)dx\int \left(- 2 \sin{\left(3 x \right)}\right)\, dx = - 2 \int \sin{\left(3 x \right)}\, dx

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

            sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

            1. The integral of sine is negative cosine:

              sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

            So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

          Now substitute uu back in:

          cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

        So, the result is: 2cos(3x)3\frac{2 \cos{\left(3 x \right)}}{3}

      The result is: x2cos(3x)3+2xsin(3x)94xcos(3x)3+4sin(3x)9+20cos(3x)27- \frac{x^{2} \cos{\left(3 x \right)}}{3} + \frac{2 x \sin{\left(3 x \right)}}{9} - \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9} + \frac{20 \cos{\left(3 x \right)}}{27}

    Method #2

    1. Use integration by parts:

      udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

      Let u(x)=x2+4x2u{\left(x \right)} = x^{2} + 4 x - 2 and let dv(x)=sin(3x)\operatorname{dv}{\left(x \right)} = \sin{\left(3 x \right)}.

      Then du(x)=2x+4\operatorname{du}{\left(x \right)} = 2 x + 4.

      To find v(x)v{\left(x \right)}:

      1. Let u=3xu = 3 x.

        Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

        sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

          sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

          1. The integral of sine is negative cosine:

            sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

          So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

        Now substitute uu back in:

        cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

      Now evaluate the sub-integral.

    2. Use integration by parts:

      udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

      Let u(x)=2x343u{\left(x \right)} = - \frac{2 x}{3} - \frac{4}{3} and let dv(x)=cos(3x)\operatorname{dv}{\left(x \right)} = \cos{\left(3 x \right)}.

      Then du(x)=23\operatorname{du}{\left(x \right)} = - \frac{2}{3}.

      To find v(x)v{\left(x \right)}:

      1. Let u=3xu = 3 x.

        Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

        cos(u)3du\int \frac{\cos{\left(u \right)}}{3}\, du

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

          cos(u)du=cos(u)du3\int \cos{\left(u \right)}\, du = \frac{\int \cos{\left(u \right)}\, du}{3}

          1. The integral of cosine is sine:

            cos(u)du=sin(u)\int \cos{\left(u \right)}\, du = \sin{\left(u \right)}

          So, the result is: sin(u)3\frac{\sin{\left(u \right)}}{3}

        Now substitute uu back in:

        sin(3x)3\frac{\sin{\left(3 x \right)}}{3}

      Now evaluate the sub-integral.

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

      (2sin(3x)9)dx=2sin(3x)dx9\int \left(- \frac{2 \sin{\left(3 x \right)}}{9}\right)\, dx = - \frac{2 \int \sin{\left(3 x \right)}\, dx}{9}

      1. Let u=3xu = 3 x.

        Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

        sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

          sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

          1. The integral of sine is negative cosine:

            sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

          So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

        Now substitute uu back in:

        cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

      So, the result is: 2cos(3x)27\frac{2 \cos{\left(3 x \right)}}{27}

    Method #3

    1. Rewrite the integrand:

      ((x2+4x)2)sin(3x)=x2sin(3x)+4xsin(3x)2sin(3x)\left(\left(x^{2} + 4 x\right) - 2\right) \sin{\left(3 x \right)} = x^{2} \sin{\left(3 x \right)} + 4 x \sin{\left(3 x \right)} - 2 \sin{\left(3 x \right)}

    2. Integrate term-by-term:

      1. Use integration by parts:

        udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

        Let u(x)=x2u{\left(x \right)} = x^{2} and let dv(x)=sin(3x)\operatorname{dv}{\left(x \right)} = \sin{\left(3 x \right)}.

        Then du(x)=2x\operatorname{du}{\left(x \right)} = 2 x.

        To find v(x)v{\left(x \right)}:

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

            sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

            1. The integral of sine is negative cosine:

              sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

            So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

          Now substitute uu back in:

          cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

        Now evaluate the sub-integral.

      2. Use integration by parts:

        udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

        Let u(x)=2x3u{\left(x \right)} = - \frac{2 x}{3} and let dv(x)=cos(3x)\operatorname{dv}{\left(x \right)} = \cos{\left(3 x \right)}.

        Then du(x)=23\operatorname{du}{\left(x \right)} = - \frac{2}{3}.

        To find v(x)v{\left(x \right)}:

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          cos(u)3du\int \frac{\cos{\left(u \right)}}{3}\, du

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

            cos(u)du=cos(u)du3\int \cos{\left(u \right)}\, du = \frac{\int \cos{\left(u \right)}\, du}{3}

            1. The integral of cosine is sine:

              cos(u)du=sin(u)\int \cos{\left(u \right)}\, du = \sin{\left(u \right)}

            So, the result is: sin(u)3\frac{\sin{\left(u \right)}}{3}

          Now substitute uu back in:

          sin(3x)3\frac{\sin{\left(3 x \right)}}{3}

        Now evaluate the sub-integral.

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

        (2sin(3x)9)dx=2sin(3x)dx9\int \left(- \frac{2 \sin{\left(3 x \right)}}{9}\right)\, dx = - \frac{2 \int \sin{\left(3 x \right)}\, dx}{9}

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

            sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

            1. The integral of sine is negative cosine:

              sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

            So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

          Now substitute uu back in:

          cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

        So, the result is: 2cos(3x)27\frac{2 \cos{\left(3 x \right)}}{27}

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

        4xsin(3x)dx=4xsin(3x)dx\int 4 x \sin{\left(3 x \right)}\, dx = 4 \int x \sin{\left(3 x \right)}\, dx

        1. Use integration by parts:

          udv=uvvdu\int \operatorname{u} \operatorname{dv} = \operatorname{u}\operatorname{v} - \int \operatorname{v} \operatorname{du}

          Let u(x)=xu{\left(x \right)} = x and let dv(x)=sin(3x)\operatorname{dv}{\left(x \right)} = \sin{\left(3 x \right)}.

          Then du(x)=1\operatorname{du}{\left(x \right)} = 1.

          To find v(x)v{\left(x \right)}:

          1. Let u=3xu = 3 x.

            Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

            sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

              sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

              1. The integral of sine is negative cosine:

                sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

              So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

            Now substitute uu back in:

            cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

          Now evaluate the sub-integral.

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

          (cos(3x)3)dx=cos(3x)dx3\int \left(- \frac{\cos{\left(3 x \right)}}{3}\right)\, dx = - \frac{\int \cos{\left(3 x \right)}\, dx}{3}

          1. Let u=3xu = 3 x.

            Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

            cos(u)3du\int \frac{\cos{\left(u \right)}}{3}\, du

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

              cos(u)du=cos(u)du3\int \cos{\left(u \right)}\, du = \frac{\int \cos{\left(u \right)}\, du}{3}

              1. The integral of cosine is sine:

                cos(u)du=sin(u)\int \cos{\left(u \right)}\, du = \sin{\left(u \right)}

              So, the result is: sin(u)3\frac{\sin{\left(u \right)}}{3}

            Now substitute uu back in:

            sin(3x)3\frac{\sin{\left(3 x \right)}}{3}

          So, the result is: sin(3x)9- \frac{\sin{\left(3 x \right)}}{9}

        So, the result is: 4xcos(3x)3+4sin(3x)9- \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9}

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

        (2sin(3x))dx=2sin(3x)dx\int \left(- 2 \sin{\left(3 x \right)}\right)\, dx = - 2 \int \sin{\left(3 x \right)}\, dx

        1. Let u=3xu = 3 x.

          Then let du=3dxdu = 3 dx and substitute du3\frac{du}{3}:

          sin(u)3du\int \frac{\sin{\left(u \right)}}{3}\, du

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

            sin(u)du=sin(u)du3\int \sin{\left(u \right)}\, du = \frac{\int \sin{\left(u \right)}\, du}{3}

            1. The integral of sine is negative cosine:

              sin(u)du=cos(u)\int \sin{\left(u \right)}\, du = - \cos{\left(u \right)}

            So, the result is: cos(u)3- \frac{\cos{\left(u \right)}}{3}

          Now substitute uu back in:

          cos(3x)3- \frac{\cos{\left(3 x \right)}}{3}

        So, the result is: 2cos(3x)3\frac{2 \cos{\left(3 x \right)}}{3}

      The result is: x2cos(3x)3+2xsin(3x)94xcos(3x)3+4sin(3x)9+20cos(3x)27- \frac{x^{2} \cos{\left(3 x \right)}}{3} + \frac{2 x \sin{\left(3 x \right)}}{9} - \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9} + \frac{20 \cos{\left(3 x \right)}}{27}

  2. Add the constant of integration:

    x2cos(3x)3+2xsin(3x)94xcos(3x)3+4sin(3x)9+20cos(3x)27+constant- \frac{x^{2} \cos{\left(3 x \right)}}{3} + \frac{2 x \sin{\left(3 x \right)}}{9} - \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9} + \frac{20 \cos{\left(3 x \right)}}{27}+ \mathrm{constant}


The answer is:

x2cos(3x)3+2xsin(3x)94xcos(3x)3+4sin(3x)9+20cos(3x)27+constant- \frac{x^{2} \cos{\left(3 x \right)}}{3} + \frac{2 x \sin{\left(3 x \right)}}{9} - \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9} + \frac{20 \cos{\left(3 x \right)}}{27}+ \mathrm{constant}

The answer (Indefinite) [src]
  /                                                                                                     
 |                                                                             2                        
 | / 2          \                   4*sin(3*x)   20*cos(3*x)   4*x*cos(3*x)   x *cos(3*x)   2*x*sin(3*x)
 | \x  + 4*x - 2/*sin(3*x) dx = C + ---------- + ----------- - ------------ - ----------- + ------------
 |                                      9             27            3              3             9      
/                                                                                                       
((x2+4x)2)sin(3x)dx=Cx2cos(3x)3+2xsin(3x)94xcos(3x)3+4sin(3x)9+20cos(3x)27\int \left(\left(x^{2} + 4 x\right) - 2\right) \sin{\left(3 x \right)}\, dx = C - \frac{x^{2} \cos{\left(3 x \right)}}{3} + \frac{2 x \sin{\left(3 x \right)}}{9} - \frac{4 x \cos{\left(3 x \right)}}{3} + \frac{4 \sin{\left(3 x \right)}}{9} + \frac{20 \cos{\left(3 x \right)}}{27}
The graph
0.001.000.100.200.300.400.500.600.700.800.902-2
The answer [src]
  20   25*cos(3)   2*sin(3)
- -- - --------- + --------
  27       27         3    
2027+2sin(3)325cos(3)27- \frac{20}{27} + \frac{2 \sin{\left(3 \right)}}{3} - \frac{25 \cos{\left(3 \right)}}{27}
=
=
  20   25*cos(3)   2*sin(3)
- -- - --------- + --------
  27       27         3    
2027+2sin(3)325cos(3)27- \frac{20}{27} + \frac{2 \sin{\left(3 \right)}}{3} - \frac{25 \cos{\left(3 \right)}}{27}
-20/27 - 25*cos(3)/27 + 2*sin(3)/3
Numerical answer [src]
0.269998983706991
0.269998983706991
The graph
Integral of (x^2+4x-2)sin3xdx dx

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