[計量] pp2-DS-167

[pilichat (人生需要不斷冒險)]

167.    16727-!-item-!-187;#058&011198
A certain circular area has its center at point P and has radius 4,
and points X and Y lie in the same plane as the circular area.
Does point Y lie outside the circular area?

(1)  The distance between point P and point X is 4.5.

(2)  The distance between point X and point Y is 9.

答案是 C

為和不是E?
條件1會知道X一定在圓外,但不知Y
條件2只知道XY沒用

但條件合起來,
只說兩點和這個原在同一平面
Y可以是任意點吧？
為和一定要切過圓？

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推 pentimento:你先劃個P為圓心，半徑為4的圓。然後在距離圓周0.5處，
→ pentimento:隨便點一個點，叫做X。然後以X為圓心，半徑為9畫一個
→ pentimento:圓，Y就是圓周上的任何一個點，你看看會在舊圓裡，還是
→ pentimento:圓外。不知這樣有沒有解了你的問題。