Re: [幾何] 高中
: 有請神人求解
設長方形底邊為2a
=> 長方形高為sqrt(100 - a^2)
a^2 + (100 - a^2) >= 2 sqrt(a^2 * (100 - a^2))
= 2a sqrt(100 - a^2)
= A
所以長方形面積極大值 = 100
此時 a^2 = 50
=> 長方形的長 = 2a = 2sqrt(50)
高為sqrt(100 - 50) = sqrt(50)
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