Einstein velocity addition solving for v

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The discussion focuses on solving the Einstein velocity addition formula, specifically finding v in terms of u and w. The formula presented is w = (u + v) / (1 + uv), leading to the rearrangement v = (w - u) / (1 - uw). Participants also inquire about the use of LaTeX outside of specialized forums, noting its importance in scientific writing. The conversation highlights the mathematical manipulations necessary to derive the desired variable. Overall, the thread emphasizes the relevance of LaTeX for clarity in scientific communication.
gtguhoij
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Homework Statement
I am trying to solve for v in the equation below. I just want to confirm I got the correct answer. Can someone confirm? If my writing is to messy I will type it. Just let me know if you can read it?
Relevant Equations
## w = \frac {u+v} {uv+1}##
 
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If my writing is to messy
It is.
 
## w = \frac {u+v} {uv+1} = ##
## \frac {w} {u+v} = \frac {1} {uv+1} = ##
## \frac {w} {u} = \frac {1} {(uv+1) -v} = ##
## \frac {w} {u} = \frac {1} {(-uv^2-v)} =##
## \frac {w} {u} = \frac {1} {(-uv^2-v)} =##
## \frac {vw} {u} = \frac {v} {(-uv^2-v)} = ##
## \frac {vw} {u} = \frac {-v} {(-uv^2-v)} = ##
## \frac {vw} {u} = \frac {-v} {(-uv^2-v)} ##
## \frac {uvw} {u} = \frac {-vu} {(-uv^2-v)} ##
## \frac {uvw} {u} = \frac {-v} {(-v^2-v)} =##
## \frac {uvw} {u} = \frac {-v} {(-v^2-v)} =##
## \frac {u} {uvw}= \frac {(-v^2-v)} {-v} = ##
## \frac {u} {uvw-v}= {(-v^2-v)} =##
## \frac {-vu} {uvw}= \frac {-v} {(-v^2-v)} =##
## \frac {-u} {uw}= \frac {1} {(v+1)} =##
## \frac {-u} {uw-1}= \frac {1} {(v)} =##
## \frac {-u} {uw-1}= \frac {1} {(v)} =## ## \frac {uw+1} {u} = {(v)} ##

Is there any way to use latex outside the physics forum?
 
Are you trying to solve for ##v## in terms of ##u## and ##w##? Quicker is:
$$\frac{u + v}{1 + uv} = w \ \Rightarrow \ u + v = w + uvw \ \Rightarrow \ v(1 -uw) = w - u \ \Rightarrow \ v = \frac{w - u}{1 - uw}$$
 
gtguhoij said:
Is there any way to use latex outside the physics forum?
It's more or less the standard for scientific writing

##\ ##
 
Thread 'Chain falling out of a horizontal tube onto a table'
My attempt: Initial total M.E = PE of hanging part + PE of part of chain in the tube. I've considered the table as to be at zero of PE. PE of hanging part = ##\frac{1}{2} \frac{m}{l}gh^{2}##. PE of part in the tube = ##\frac{m}{l}(l - h)gh##. Final ME = ##\frac{1}{2}\frac{m}{l}gh^{2}## + ##\frac{1}{2}\frac{m}{l}hv^{2}##. Since Initial ME = Final ME. Therefore, ##\frac{1}{2}\frac{m}{l}hv^{2}## = ##\frac{m}{l}(l-h)gh##. Solving this gives: ## v = \sqrt{2g(l-h)}##. But the answer in the book...