Suppose you're sauntering about Saint-Germain, Paris, from one cafe to the next, staying only as long as it takes you to knock down a few Brilliant problems. You're wrapping up at Brasserie Lipp and want to go to Cafè de Flore, which is across the road.
The only problem is: it's pouring rain!
If you want to make it from one cafe to the next while staying as dry as possible, how should you move?
- \(v_r\) and \(v_w\) are the speeds at which you can run or walk across the road, respectively, with \(v_w < v_r\).