Can This Differential Equation Solution Be Simplified Further?

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Discussion Overview

The discussion revolves around the simplification of a solution to a differential equation involving the expression dy/(y^2 - 4) = dx. Participants explore various methods of integration and potential simplifications, focusing on the correctness of the steps taken and alternative approaches.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant presents a solution involving logarithmic manipulation and asks if it can be simplified further.
  • Another participant points out mismatched parentheses and suggests using the substitution y = 2sec(t) for integration.
  • A different participant proposes the use of partial fractions as a method to separate the terms in the denominator.
  • Concerns are raised about the clarity of the original post and the correctness of the multiplication step involving "-4".

Areas of Agreement / Disagreement

Participants express differing views on the methods used for integration and the correctness of the initial solution. There is no consensus on the best approach or the validity of the steps taken.

Contextual Notes

Some participants note issues with the presentation of the mathematical expressions, including mismatched parentheses and unclear steps in the solution process. There is also uncertainty regarding the application of partial fractions and the substitution method suggested.

Naeem
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I did the following:

dy/(y^2 -4 ) = dx

Integral ( -1/4 /y + 2 + 1/4 / ( y-2) . dy = Integral dx

-1/4 ln | y + 2 | + 1 /4 ln |y -2 | + C = x

Multiplying all thru by - 4 we get

ln | y + 2 | + ln | y - 2 | + 4C = 4x ( Note: 4C is another 'C'which is a bigger C)

ln | y + 2 / y - 2| + C = 4x

C = 4x - ln | y + 2 / y -2 |

If this is correct, can we simplify the solution any further.
 
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You ahve a lot of mismatched parentheses but,

[tex]\frac{1}{y^2-4} = \frac{1}{(y-2)(y+2)}[/tex]

You can't separate these two in the denominator.

I would do this using the substitution y = 2sec(t)
 
Why not? Using Partial fractions you could

A/ something + B / something
 
I don't think that's what he did, or if he did he didnt show the work. I can barely read his post.
 
That "-4" multiplication is incorreclty made.You should have other signs...

Daniel.
 

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