00:01
So for this problem, first we will prove the following inequality.
00:06
Sum i from 1 to k, n -square, is less than n -square minus k -1, multiply 2m minus k.
00:21
We will prove this inequality by induction on k.
00:34
So first, if k is equal to 1, left -hand side is equal to n square and right hand side is also n squared so n square is less than n squared is true to assume k is equal to p this inequality oath then for k equal to p plus one we have some i from 1 to p plus 1, an i square, and this is equal to n p plus 1 square, plus sum i from 1 to p, and i square.
01:41
And for this part, we use the assumption.
01:45
So this is a lesson or equal to np plus 1 square, plus here for this one, and 1 plus here, for this one, and 1 plus dot plus n t is equal to n minus n p plus 1.
02:10
So here this is n minus n p plus 1 square minus your k is equal to p is a p minus 1 times your n is n is n minus n times p plus 1 then minus p and here we denote this one as a function f...