摘要
假設有一點A和位置較低的點B以一條直線相連，在不考慮摩擦力的前提下，一顆靜止的滾珠由A點滑向B點，如果我們將直線換成不同均曲線試試看，以哪種線作爲路徑，花費的時間可以最少？花費的時間最少的曲線就稱爲最速降線。
關鍵字
最速降線並列摘要
Consider a point A is joined by a straight wire to a lower point B, and that a bead is allowed to slide without friction down the wire from A to B. We can also consider the case where the wire is bent into an arbitrary curve. In which case does a bead take the least time? The curve with the least time is called the brachistochrone.