圖中,A(2,4)和B(6,8)是曲綫y=x^2-7x+14上的兩點.
(a)求AB的斜率.
(b)(i)若曲綫在C點的切綫與AB平行,求C的坐標.
(ii)求曲綫在C點的切綫方程.
我計左(a)part,但bpat唔識計.
(a)答案為1,(b)(i)答案為(4,2)(ii)答案為x-y-2=0.
一題難的微分應用問題.
2007-11-14 6:14 am
回答 (1)
2007-11-14 6:23 am
✔ 最佳答案
(a) 斜率 = (8-4)/(6-2) = 4/4 =1(b)(i) 設C是(a, b)
dy/dx = 2x - 7
dy/dx|(a,b) = 2a-7 = 1
2a = 8
a=4
b = 4^2 - 7(4) + 14 = 16-28+14 = 2
C是(4, 2)
y-2 = 1(x-4)
x-y-4+2 = 0
x-y-2 =0
收錄日期: 2021-04-13 18:13:14
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https://hk.answers.yahoo.com/question/index?qid=20071113000051KK04188