Hi,
For this question, the answer claims that the limit of (s-r) is a positive number less than 1.
I can understand the part about less than one, since the triangle inequality gives r+1>s => 1>s-r.
However, how do we prove that it must be positive (>0) and cannot be zero?
Thanks a lot for help.
Rigorous proof of Q39 (infinite triangle question)
-
- Posts: 61
- Joined: Sun Apr 04, 2010 1:08 pm
Re: Rigorous proof of Q39 (infinite triangle question)
Project s down to the "x-axis". Then |proj_r(s)| <= s, but proj_r(s) - r = some constant > 0 for all r. Thus lim s -r > lim proj_r(s) - r > 0.