🚀 go-pugleaf

In article <gripD6D4JB.28n@netcom.com>,  <grip@netcom.com> wrote:
:>I suspect the original poser of the question simply had in mind that the 
:>slope was always negative. This surely gives one a nice minimum and 
:>should be intuitively solvable by many first year algebra students.
:>
:>Alternatively it could have been stated with both A and B positive.
:>

A challenging re-formulation: A line segment of length d slides in the 
plane so that its endpoints stay on the nonnegative semiaxes of the 
rectangular coordinate system. 
(1) Describe the boundary of the region swept by the segment,
(2) find out for what value of d, the region's boundary passes through 
    (2,2) (or any other given point inside the first quadrant).

Think of (idealizing the situation) a beam being carried horizontally
around a corner of a corridor; how long can the beam be, so that it still
does not scratch the corner? (An answer will be, of course, an inequality 
d < d(critical).)

|     |
|\    |
|  \  |  (a,b), for example (2,2)
|    \L_____________
|      \  (oops!)
L________\___________

(An amusing detail: The spelling checker considered the word "oops" 
misspelled.)

Have fun with this one, Slavek (ZVK).