The perimeter of a rectangle is 72m. What are its dimensions that yield the maximum area?
问题描述：
The perimeter of a rectangle is 72m. What are its dimensions that yield the maximum area?
答
矩形周长为72cm,当长为多少时面积最大?
当其为正方形时,即 长=宽=18cm时 Smax=18*18=324cm(平方厘米)如果用导数方法，那要怎麼做？用导数。饶了我吧。早就还给老师喽。呵呵anyway，你还是解答得很好