Integration

[starbaj12]

from r to R e^(-2r/a)*r^2 dr

Thanks

[dextercioby]

from r to R e^(-2r/a)*r^2 dr

Thanks

U're one lazy dude... :yuck: Two times part integration,pay attention to signs and integration limits.
Daniel.

[HallsofIvy]

Looks pretty standard to me.

Use "integration by parts", twice.

If you let u= r2 and dv= e-2r/a, then du= 2r dr and
v= -a/2 e-2r/a

Now you have an integral of e-2r/ar and integrating by parts again will give you an integral with just e-2r/a.