Date: MATH 1210-4 - Spring 2004
Note: Unless stated otherwise, answers without justification receive no credit. Please, show your work!
Since is close to , whose square root is , we use the formula
Using the calculator we obtain the value (rounded to five decimal places) .
Figure 1 shows the graph where is the distance from the airplane to the observer and is the (horizontal) distance traveled by the airplane from the moment it passed over the observer.
We know that and we want to know one minute after the plane flew over the observer. Since the plane travels miles per minute, we want to know when .
For all times we have the relation , so that, taking derivatives (with respect to time, ) on both sides we get