唔明...
一輛貨車從甲地到乙地需8小時，一輛客車從乙地到甲地需6小時，貨車開了兩小時後，客車出發，問客車出發後幾小時兩車相遇？解 這題與一般的相遇問題不同，全程多少，沒有具體的量，這時可以設甲地到乙地的路程為“１”，這樣就把行程問題轉化成了工程問題。
貨車一小時走全程的1/8，客車一小時走全程的1/6，貨車走了兩小時後，還有路程為
１－１ 咁唔明d咩[] 簡單黎講...當全程為 1...
呢條問題,最後全程係會被cancel走,所以是independent的.
就算你let x, 都無問題.
speed A = x/8
speed B = x/6
distance travelled by A in 2 hrs = 2x/8
remaining distance= x - 2x/6
-----------------------------------------------------------------------------------------------
relative speed = x/6 + x/8
time to meet = (x - 2x/8) / (x/6 + x/8) = 18/7 hrs
or
let t be the time to meet, sum of distance travel = remaining distance
xt/6 + xt/8 = x - 2x/6
u will also get the same result by the same calculation after rearrangment.
[ 本帖最後由 【YU】 於 27-5-2008 10:38 編輯 ] 冇野...
明了
睇唔到呢句...--->貨車開了兩小時後....
THX~~~
[ 本帖最後由 L.K. 於 27-5-2008 12:37 編輯 ] 原帖由 【YU】 於 27-5-2008 10:32 發表 http://www.nakuz.com/bbs/images/common/back.gif
簡單黎講...當全程為 1...
呢條問題,最後全程係會被cancel走,所以是independent的.
就算你let x, 都無問題.
speed A = x/8
speed B = x/6
distance travelled by A in 2 hrs = 2x/8
remaining distance= x ...
高人果然唔同d[] 一睇就知佢唔明d咩 梗係啦 神級學長YU就好啦 考完試....
1614 1614 1614 原帖由 adamsteve 於 27-5-2008 17:02 發表 http://www.nakuz.com/bbs/images/common/back.gif
梗係啦 神級學長YU就好啦 考完試....
1614 1614 1614
1614的意思是否
BEng (Hons) Mechatronic Engineering?[]樂古真係好多Engine ge人才 1614 = ELEC1614 = Course Code of Electronic devices and circuits of EE in HKU....
wt is Mechatronic Engineering ? new thing? 原帖由 【YU】 於 27-5-2008 17:54 發表 http://www.nakuz.com/bbs/images/common/back.gif
1614 = ELEC1614 = Course Code of Electronic devices and circuits of EE in HKU....
wt is Mechatronic Engineering ? new thing?
唔知wor,路過jupas見到...
其實可能Adamsteve只係求其up d無意思ge數字出泥[]
[ 本帖最後由 piyopiyo 於 27-5-2008 18:06 編輯 ] 唔會啦@@ yu 1614 拎a+架=.=
1614可以話係圍內暗號 原來人地學系係記course名
係好少記course code=.= 搞到我變左異族咁
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