How do you find the integral ln x / x^(1/2)?

2 Answers
Apr 10, 2018

intlnx/x^(1/2)dx=2sqrtxlnx-4sqrtx+C

Explanation:

Rewrite the integrand, and integrate by parts:

intlnx/x^(1/2)dx=intx^(-1/2)lnxdx

u=lnx

du=x^-1dx

dv=x^(-1/2)dx

v=intx^(-1/2)dx=2x^(1/2)

uv-intvdu=2sqrtxlnx-2intx^(1/2)x^-1dx

=2sqrtxlnx-2intx^(-1/2)dx=2sqrtxlnx-4sqrtx+C

So,

intlnx/x^(1/2)dx=2sqrtxlnx-4sqrtx+C

Apr 10, 2018

2sqrtxInx-4sqrtx + C

Explanation:

Let u=Inx
and dv=x^(-1/2) SO v=2sqrtx

Integration by parts = uv-int v du

int(Inx)/x^(1/2) dx = 2sqrtxtimes Inx - int 2sqrtx times 1/x

=2sqrtxInx-2intx^(-1/2) dx

=2sqrtxInx-2times2sqrtx + C

=2sqrtxInx-4sqrtx + C