I 'm currently working on my exercise, the question is
L1: 3x + y - 4 = 0 and
L2: 3x - y + 3 = 0 are given.
P (h,k) is a point on the line x - y + 1 = 0.
Suppose the distances of P from L1 and L2 are d1 and d2 respectively.
(a) Express k in terms of h.
>> I 've got it: k = h + 1
(b) Express d1 + d2 in terms of h.
>> That's easy as well.
ie. 1/(10)^(1/2) (|4h + 3| + |2h + 2|)
(c) When d1 + d2 is at the minimum, what is the value of h?
Find also the value of d1 + d2 and the coordinates of P at this instance.
>> This 's my problem. I got stuck and have no idea at all.
Please kindly help me.