標題:
F3 coordinate question (2)
發問:
Given three points A(0,1) , P(x,0) and B(5,3), find the least value of PA+PB in surd form, and the corresponding value of x.
最佳解答:
PA + PB has the least value when (x - 0)/(5 - x) = (1 - 0)/(3 - 0) ==> 3x = 5 - x ==> x = 5/4 PA + PB = √[(5/4 - 0)^2 + (0 - 1)^2]) + √[(5 - 5/4)^2 + (3 - 0)^2] = √41/16 + √369/16 = √41/16 + √369/16 = √41 Therefore, the least value of PA + PB is √41, and the corresponding value of x is 5/4.
此文章來自奇摩知識+如有不便請留言告知
其他解答:
文章標籤
全站熱搜
留言列表
