Question

What is the value of 1*1! + 2*2! + 3!*3! + ............ n*n! ?

Answer 1

nikvist can u help me??

Answer 2

\[S_n=\sum\limits_{k=1}^{n}k\cdot k!=\sum\limits_{k=1}^{n}(k+1-1)\cdot k!=\sum\limits_{k=1}^{n}(k+1)!-\sum\limits_{k=1}^{n}k!=\]\[=(n+1)!-1\]

Answer 3

ok, AravindG !!! I will help you

Answer 4

:)

Answer 5

http://openstudy.com/groups/mathematics/updates/4e74cb580b8b7d4f6cf764b4#/groups/mathematics/updates/4e788d550b8b7d4f6d15e36d