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Integral of ((ln(2x))^2)/x dx

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01log(2x)2xdx\int\limits_{0}^{1} \frac{\log{\left(2 x \right)}^{2}}{x}\, dx
Integral(log(2*x)^2/x, (x, 0, 1))
Detail solution
  1. There are multiple ways to do this integral.

    Method #1

    1. Let u=log(2x)u = \log{\left(2 x \right)}.

      Then let du=dxxdu = \frac{dx}{x} and substitute dudu:

      u2du\int u^{2}\, du

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

        u2du=u33\int u^{2}\, du = \frac{u^{3}}{3}

      Now substitute uu back in:

      log(2x)33\frac{\log{\left(2 x \right)}^{3}}{3}

    Method #2

    1. Rewrite the integrand:

      log(2x)2x=log(x)2+2log(2)log(x)+log(2)2x\frac{\log{\left(2 x \right)}^{2}}{x} = \frac{\log{\left(x \right)}^{2} + 2 \log{\left(2 \right)} \log{\left(x \right)} + \log{\left(2 \right)}^{2}}{x}

    2. Let u=1xu = \frac{1}{x}.

      Then let du=dxx2du = - \frac{dx}{x^{2}} and substitute dudu:

      log(1u)22log(2)log(1u)log(2)2udu\int \frac{- \log{\left(\frac{1}{u} \right)}^{2} - 2 \log{\left(2 \right)} \log{\left(\frac{1}{u} \right)} - \log{\left(2 \right)}^{2}}{u}\, du

      1. Let u=log(1u)u = \log{\left(\frac{1}{u} \right)}.

        Then let du=duudu = - \frac{du}{u} and substitute dudu:

        (u2+2ulog(2)+log(2)2)du\int \left(u^{2} + 2 u \log{\left(2 \right)} + \log{\left(2 \right)}^{2}\right)\, du

        1. Integrate term-by-term:

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

            u2du=u33\int u^{2}\, du = \frac{u^{3}}{3}

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

            2ulog(2)du=2log(2)udu\int 2 u \log{\left(2 \right)}\, du = 2 \log{\left(2 \right)} \int u\, du

            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: u2log(2)u^{2} \log{\left(2 \right)}

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

            log(2)2du=ulog(2)2\int \log{\left(2 \right)}^{2}\, du = u \log{\left(2 \right)}^{2}

          The result is: u33+u2log(2)+ulog(2)2\frac{u^{3}}{3} + u^{2} \log{\left(2 \right)} + u \log{\left(2 \right)}^{2}

        Now substitute uu back in:

        log(1u)33+log(2)log(1u)2+log(2)2log(1u)\frac{\log{\left(\frac{1}{u} \right)}^{3}}{3} + \log{\left(2 \right)} \log{\left(\frac{1}{u} \right)}^{2} + \log{\left(2 \right)}^{2} \log{\left(\frac{1}{u} \right)}

      Now substitute uu back in:

      log(x)33+log(2)log(x)2+log(2)2log(x)\frac{\log{\left(x \right)}^{3}}{3} + \log{\left(2 \right)} \log{\left(x \right)}^{2} + \log{\left(2 \right)}^{2} \log{\left(x \right)}

    Method #3

    1. Rewrite the integrand:

      log(2x)2x=log(x)2x+2log(2)log(x)x+log(2)2x\frac{\log{\left(2 x \right)}^{2}}{x} = \frac{\log{\left(x \right)}^{2}}{x} + \frac{2 \log{\left(2 \right)} \log{\left(x \right)}}{x} + \frac{\log{\left(2 \right)}^{2}}{x}

    2. Integrate term-by-term:

      1. Let u=1xu = \frac{1}{x}.

        Then let du=dxx2du = - \frac{dx}{x^{2}} and substitute du- du:

        log(1u)2udu\int \frac{\log{\left(\frac{1}{u} \right)}^{2}}{u}\, du

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

          (log(1u)2u)du=log(1u)2udu\int \left(- \frac{\log{\left(\frac{1}{u} \right)}^{2}}{u}\right)\, du = - \int \frac{\log{\left(\frac{1}{u} \right)}^{2}}{u}\, du

          1. Let u=log(1u)u = \log{\left(\frac{1}{u} \right)}.

            Then let du=duudu = - \frac{du}{u} and substitute du- du:

            u2du\int u^{2}\, du

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

              (u2)du=u2du\int \left(- u^{2}\right)\, du = - \int u^{2}\, du

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

                u2du=u33\int u^{2}\, du = \frac{u^{3}}{3}

              So, the result is: u33- \frac{u^{3}}{3}

            Now substitute uu back in:

            log(1u)33- \frac{\log{\left(\frac{1}{u} \right)}^{3}}{3}

          So, the result is: log(1u)33\frac{\log{\left(\frac{1}{u} \right)}^{3}}{3}

        Now substitute uu back in:

        log(x)33\frac{\log{\left(x \right)}^{3}}{3}

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

        2log(2)log(x)xdx=2log(2)log(x)xdx\int \frac{2 \log{\left(2 \right)} \log{\left(x \right)}}{x}\, dx = 2 \log{\left(2 \right)} \int \frac{\log{\left(x \right)}}{x}\, dx

        1. Let u=1xu = \frac{1}{x}.

          Then let du=dxx2du = - \frac{dx}{x^{2}} and substitute du- du:

          log(1u)udu\int \frac{\log{\left(\frac{1}{u} \right)}}{u}\, du

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

            (log(1u)u)du=log(1u)udu\int \left(- \frac{\log{\left(\frac{1}{u} \right)}}{u}\right)\, du = - \int \frac{\log{\left(\frac{1}{u} \right)}}{u}\, du

            1. Let u=log(1u)u = \log{\left(\frac{1}{u} \right)}.

              Then let du=duudu = - \frac{du}{u} and substitute du- du:

              udu\int u\, du

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

                (u)du=udu\int \left(- u\right)\, du = - \int u\, du

                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: u22- \frac{u^{2}}{2}

              Now substitute uu back in:

              log(1u)22- \frac{\log{\left(\frac{1}{u} \right)}^{2}}{2}

            So, the result is: log(1u)22\frac{\log{\left(\frac{1}{u} \right)}^{2}}{2}

          Now substitute uu back in:

          log(x)22\frac{\log{\left(x \right)}^{2}}{2}

        So, the result is: log(2)log(x)2\log{\left(2 \right)} \log{\left(x \right)}^{2}

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

        log(2)2xdx=log(2)21xdx\int \frac{\log{\left(2 \right)}^{2}}{x}\, dx = \log{\left(2 \right)}^{2} \int \frac{1}{x}\, dx

        1. The integral of 1x\frac{1}{x} is log(x)\log{\left(x \right)}.

        So, the result is: log(2)2log(x)\log{\left(2 \right)}^{2} \log{\left(x \right)}

      The result is: log(x)33+log(2)log(x)2+log(2)2log(x)\frac{\log{\left(x \right)}^{3}}{3} + \log{\left(2 \right)} \log{\left(x \right)}^{2} + \log{\left(2 \right)}^{2} \log{\left(x \right)}

  2. Add the constant of integration:

    log(2x)33+constant\frac{\log{\left(2 x \right)}^{3}}{3}+ \mathrm{constant}


The answer is:

log(2x)33+constant\frac{\log{\left(2 x \right)}^{3}}{3}+ \mathrm{constant}

The answer (Indefinite) [src]
  /                            
 |                             
 |    2                  3     
 | log (2*x)          log (2*x)
 | --------- dx = C + ---------
 |     x                  3    
 |                             
/                              
(log(2x))33{{\left(\log \left(2\,x\right)\right)^3}\over{3}}
The answer [src]
oo
%a{\it \%a}
=
=
oo
\infty
Numerical answer [src]
27242.1350802983
27242.1350802983

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