Take the 2-minute tour ×
Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Please look at the diagram:

img

I know $D$, $\alpha$ and $\theta$. I also know the $a/b$ ratio of $k$. I don't know $c$. Can I find out $a$ or $b$ or $a+b$?

share|improve this question
4  
It would have been good style to mention this directly related question: math.stackexchange.com/questions/59636/can-i-find-the-angle/… to avoid unnecessary duplication of efforts. –  joriki Aug 25 '11 at 8:04
    
sorry this is a different question.. they may look similar but nothing is far from truth.. –  Frank Aug 25 '11 at 8:25
    
I can see it's a different question; otherwise I would have voted to close it as a duplicate. Nevertheless it's clear that some insight might be gained from answers to the other question, and there's no reason not to include a link. –  joriki Aug 25 '11 at 8:30
    
What is $\alpha$? An angle? –  Peter Taylor Aug 25 '11 at 8:57
    
α is the angle.. Sorry it wasn't clear. –  Frank Aug 25 '11 at 9:03

1 Answer 1

up vote 3 down vote accepted

This is a slightly different question to this one. But the answer is the same: it is not possible to determine $a$ or $b$ or $a+b$. Look at this figure:

enter image description here

We can move the red lines anywhere in the $\theta$ cone without changing $\alpha$ and $k=a/b$. But $a$ and $b$ are changed.

share|improve this answer
    
Thanks for the answer.. It is clear this is not possible. –  Frank Aug 25 '11 at 9:25

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.