That's the average speed it's falling from the interval x=[8-10], not the speed it's falling at a given point.
Think about it like this, you go out driving, starting at 0 mph, and end up going 60 miles in one hour, giving you an average speed of 60 mph's, but you didn't start ...
@BarbierNicholas
That's the average speed it's falling from the interval x=[8-10], not the speed it's falling at a given point.
Think about it like this, you go out driving, starting at 0 mph, and end up going 60 miles in one hour, giving you an average speed of 60 mph's, but you didn't start ...