How Do These Algebraic Expressions Equate in an ODE Problem?

AI Thread Summary
The discussion focuses on solving an ordinary differential equation (ODE) problem involving the algebraic expressions \(\frac{y+1}{y-1} = Cx^2\) and \(y = \frac{1+Cx^2}{1-Cx^2}\). The participant is confused about the equivalence of these two forms after manipulating the equation. They mention using the technique of multiplying both sides by \(y - 1\) and rearranging terms to isolate \(y\). However, their manipulation leads to a different expression, \(y = \frac{Cx^2 + 1}{Cx^2 - 1}\), indicating a potential error in the original transformation. Clarifying these algebraic steps is essential for understanding the solution to the ODE problem.
andrew.c
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Homework Statement



I'm doing an ODE problem, and I have a set of solutions for it, but I do not understand how

\frac{y+1}{y-1} = Cx^2

can equal

y = \frac{1+Cx^2}{1-Cx^2}

Many Thanks!
 
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The basic technique is to multiply both sides by y - 1, then move all terms in y to one side and all other terms to the other side and solve for y.

For this problem, though, I get y = (Cx^2 + 1)/(Cx^2 - 1), which is different from what you showed.
 
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