Posted by
**Woof** on
.

can you help me get started on this integral by parts?

4

S sqrt(t) ln(t) dt

1

please help! thanks!

Integral t^(1/2)Ln(t)dt =

2/3 t^(3/2)Ln(t)-

2/3 Integral t^(1/2) dt =

2/3 t^(3/2)Ln(t) - 4/9 t^(3/2)

Simpler method:

Integral t^(a)dt = t^(a+1)/(a+1)

Integral d/da [t^(a)]dt =

d/da [t^(a+1)/(a+1)] ----->

Integral t^(a)Ln(t)dt =

t^(a+1)Ln(t)/(a+1) - t^(a+1)/(a+1)^2

Finally put a = 1/2.