00:01
So for this problem, we are verifying whether some inequalities are going to be equal, whether some sigmas are going to be equal or not.
00:08
And so we can go ahead and start with part a.
00:10
And we know from our rules of evaluating a series and sequences that if we are going to evaluate some variable just like this, i is equal to 1 of i to 10, essentially we're just adding up all the numbers 1 through 10.
00:26
And so since we see that this is exactly the same as the expression on the right side, except that our i is replaced by k, that tells us that these two are going to be equal.
00:37
Next for part b, which is down here, we have a series that's going to go the same as our first one, i is equal to one to ten of just i, and we're comparing this to i is equal to six through 15 of i minus five.
00:52
And so we can see that essentially this is just shifting our first series to the right.
01:01
And so basically if we were to plug in i is equal to 6 here, we would get 6 minus 5, which is equal to 1.
01:06
And in our first one, if we were to just plug in i is equal to 1, we would get 1.
01:10
And so this is going to continue all the way up through 15, which will give us a final value of 15 minus 5, which is 10.
01:17
And we know that our final in our first one will also be 10...