00:01
So today we're going to be going over the derivative at a point, but more specifically, we're going to be going over how to interpret values and rates when it comes to real -life application questions.
00:16
Both values and rates are input and output functions, where values are usually in these sorts of questions, evaluate.
00:34
At a certain point in time where you usually get some sort of output, something that you're measuring, and rates are usually given within a certain time frame, like from one year to five years in the future, and you're trying to see the change per year or per whatever time you're giving of something that you're measuring.
01:01
In this question, we're given a rate of some kind.
01:07
And we're also given that f of t is a function that measures the sea ice, the art, yeah, the sea ice extent in millions of square kilometers.
01:25
And this t here is an input of time that is measured in days after december 31st of 2014.
01:43
So since we're given that, that makes understanding these a lot easier.
01:50
So we know that this one is after 59 days after december 31st, and this one is 32 days after december 31st.
02:00
So let's do this.
02:05
We know that january has 31 days.
02:12
February has 28 days.
02:17
So let's add those two numbers up to see if we get one of the numbers up.
02:21
We're given.
02:25
So 31 plus 28...