Consider two parallel lines L1: 3x-4y-2= 0 L2: 3x-4y+13=0
(a) find the distance between L1 and L2
(b) A line L cuts L1 and L2 at P and Q respectively . if PQ = √13 and the acute angle between L and L2 isθ
(i) find tanθ
(ii) hence, find the possible value(s) of the slope of L
straight lines
2007-12-20 2:26 am
回答 (1)
2007-12-20 3:03 am
✔ 最佳答案
(a)distance=∣[13-(-2)] / √(3²+4²) ∣=∣15/5∣
=3
(b)(i)
sinθ=3/√13
tanθ=3/2
(ii)
set slope of L is m
tanθ=∣(m- L1slope) / (1+ m*L1slope) ∣
3/2 = ∣(m-3/4) / (1+3m/4) ∣
±3/2= (4m-3) / (4+3m)
12+9m=8m-6 or -12-9m=8m-6
m=-18 or -6/17
參考: me
收錄日期: 2021-04-29 20:03:36
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