00:01
All right, so we want to find the number of subscribers in 16 months, and they give us the growth rate of the number of subscribers.
00:09
So let's say the number of subscribers is s of t, what they give us is s prime of t.
00:16
And they give that to be 100 plus 210 times t to the three quarters.
00:26
And they also give us the number of subscribers we had at the beginning.
00:34
So s of zero is 5 ,000.
00:37
And we want to find s of 16.
00:39
T is measured in months.
00:41
Okay, so let's take an integral to get s of t.
00:44
It's going to be 100t plus this is going to be t to the 7 fourths.
00:51
So we've got 2 .10 times four -sevenths.
00:56
That's a reverse power rule...