Ｑ１
Two trains 80m and 100m long are travelling in opposite directions at 45km/h and 36km/h respectively. How many seconds will they take to pass each other completely？
兩列長80m及100m的火車分別以45km/h 及36km/h 的速率相對地行駛。問由相遇開始計算，它們需要若干秒會再分開？
Ｑ２
Express -32x^5/8x^3 in the simplest index form
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中四數學問題！感激
2007-06-14 2:59 am
回答 (2)
2007-06-14 3:05 am
✔ 最佳答案
Ｑ１兩列長80m及100m的火車分別以45km/h 及36km/h 的速率相對地行駛。問由相遇開始計算，它們需要若干秒會再分開？
兩者相對的速度 = 45 + 36 = 81km/h = 81/3.6(ms-1) = 22.5ms-1
(80 + 100) / 22.5
= 8秒
Ｑ２
Express -32x5/8x3 in the simplest index form
-32x5/8x3
= -4 x5-3
= -4x2
2007-06-14 3:11 am
Q.1
(80m+100m)除[(45km+36km)除60除60X1000]
=8
Q.2
-32x^5/8x^3
=-4X^2
(80m+100m)除[(45km+36km)除60除60X1000]
=8
Q.2
-32x^5/8x^3
=-4X^2
收錄日期: 2021-04-13 00:57:54
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20070613000051KK03489