Shortest surface routes
The shortest route along a box may cross two or three faces. Unfold the faces to compare straight segments.
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Compare corner routes · Choose the shortest outside route between opposite corners.
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6 questions · No time limit
Example
Example
Example · Standard
What is the shortest distance from A to B while staying on the outside surface?
A and B are opposite corners. You may use any outside face. The route cannot pass through the box.
- Questions answered
- 0 / 6
- Active time
- 0:00
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Choose an exact distance, then unfold the box and compare valid routes.
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How this data is usedHelp
Travel from A to B on the outside of the box. Unfolding faces preserves distance, so a shortest route becomes a straight segment within a valid unfolding. Compare squared lengths using the two perpendicular offsets. A straight segment that leaves the chosen faces is not a valid surface route. The square-root symbol gives an exact length; a route through the inside of the box is not allowed.
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About this practice
Learn a method
Unfold a surface routeThe shortest route along a box may cross two or three faces. Unfold the faces to compare straight segments.
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Optional and off by default. Share starts, completions, replays and error categories. For visits from ChatGPT, starts and completions can also include the first QuickenBrain page and broad country. No answers, drawings or names.
How this data is used