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karamazovnew · 07-25-10, 12:26 PM

I've played around with that GeoGebra program you sent me, what an amazing tool, I'll always keep this installed. I used my previous bearings for practice. I didn't even need to use my sub's position on the second bearing, somehow the red line always coincides with the fourth bearing. I have to admit, I feel stupid right now. Not because I was wrong before, but because I must've done SOMETHING wrong to end up with good solutions and now, for the love of God, I can't remember WHAT

. The picture I sent before was not a fake, yet time and time again I can't get that red line anymore

. It wasn't from plotting mistakes, although drawing circles so small I could've actually fulfilled the rule to change speed because of the silly 0.5 error in the SH ruler

So Makman, you have my apologies for not initially believing you. So.. on the move, after 3 bearings, we can can the 4'th. I still can't shake the feeling that knowing what distance we've traveled between readings, we could somehow protract the bearings back to our original position. That would solve this problem

.

Wait, I've just thought about a counterexample to what I've just said. Imagine moving along at a constant speed and course and all first 3 bearings are 90 degrees. This means that the 4'th will also be 90, this can either be a ship moving parallel to you at the same speed as you, or at any angle to your course but at a greater speed. Yeap, this problem is unsolvable...

07-25-10, 12:26 PM	#41
karamazovnew The Old Man Join Date: Mar 2009 Location: Bucharest, Romania Posts: 1,403 Downloads: 151 Uploads: 0	I've played around with that GeoGebra program you sent me, what an amazing tool, I'll always keep this installed. I used my previous bearings for practice. I didn't even need to use my sub's position on the second bearing, somehow the red line always coincides with the fourth bearing. I have to admit, I feel stupid right now. Not because I was wrong before, but because I must've done SOMETHING wrong to end up with good solutions and now, for the love of God, I can't remember WHAT . The picture I sent before was not a fake, yet time and time again I can't get that red line anymore . It wasn't from plotting mistakes, although drawing circles so small I could've actually fulfilled the rule to change speed because of the silly 0.5 error in the SH ruler So Makman, you have my apologies for not initially believing you. So.. on the move, after 3 bearings, we can can the 4'th. I still can't shake the feeling that knowing what distance we've traveled between readings, we could somehow protract the bearings back to our original position. That would solve this problem . Wait, I've just thought about a counterexample to what I've just said. Imagine moving along at a constant speed and course and all first 3 bearings are 90 degrees. This means that the 4'th will also be 90, this can either be a ship moving parallel to you at the same speed as you, or at any angle to your course but at a greater speed. Yeap, this problem is unsolvable... Last edited by karamazovnew; 07-25-10 at 12:47 PM.