integral [(1/120) (x^5 -20 x^4 120 x^3-240 x^2 120 x)]^3 e^-x dx ), x = 0 to oo

Uh oh! Wolfram|Alpha doesn't run without JavaScript.

Please enable JavaScript. If you don't know how, you can find instructionshere.Once you've done that, refresh this page to start using Wolfram|Alpha.