How do you integrate int ln 4x dx ln4xdx using integration by parts?

2 Answers
Apr 6, 2018

=xln4x-x+C=xln4xx+C

Explanation:

intln4xdxln4xdx

You can't integrate ln4xln4x so you pick

u=ln4xu=ln4x rarr du=1/xdxdu=1xdx
dv=dxdv=dxrarrv=xv=x

And by using the formula:
intudv=uv-intvduudv=uvvdu

intln4xdx=xln4x-intx/xdxln4xdx=xln4xxxdx

=xln4x-int1dx=xln4x1dx

=xln4x-x+C=xln4xx+C

Apr 6, 2018

The answer is =x(ln(|4x|)-1)+C=x(ln(|4x|)1)+C

Explanation:

Perform the integration by parts

intuv'=uv-intu'v

Here,

u=ln4x, =>, u'=1/(4x)*4=1/x

v'=1, =>, v=x

Therefore,

intln4x=xln4x-int1/x*xdx

=xln4x-x+C

=x(ln(|4x|)-1)+C