InterviewSolution
Saved Bookmarks
| 1. |
Find the sum (sumsum)_(0leiltjlen) ""^(n)C_(i). |
|
Answer» Solution :`UNDERSET(0leiltjlen)(sumsum).^(N)C_(i) = ((underset(i=0)overset(n)sumunderset(j=0)overset(n)sum.^(n)C_(i))-underset(i=0)overset(n)sum.^(n)C_(i))/(2)` `= ((underset(i=0)overset(n)sum(n+1)^(n)C_(i))-underset(i=0)overset(n)sum.^(n)C_(i))/(2)` ` = ((n+1)2^(n)-2^(n))/(2)` `= n xx 2^(n-1)` |
|