One mile from a house, down a straight road, is an intersection. A highway
runs through the intersection, perpendicular to the road to the house.
Suppose an automobile travels 60 mph along the highway
- How fast is the distance between the car and the house increasing when the
car is `3` miles past the intersection?
- How fast is the distance between the car and the house increasing when the
car is `x` miles past the intersection?
- Confirm your answer to the previous part by substituting `x = 3` and `x = 0`.
- Suppose the speed of the car `x` miles past the intersection is a function
`s(x)`. (So previously, `s(x) = 60` was a constant function.) Now
how fast is the distance between the car and the house increasing when the
car is `x` miles past the intersection?