General solution of differential equation

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delsoo
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Homework Statement



i can't reduce the eq to y= (X+1)/(x+c ) , which part is wrong?

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The Attempt at a Solution

 

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You already have it.
[tex]y=\frac{c(1+x)}{1+c(1+x)}[/tex]
Divide numerator and denominator by c:
[tex]y=\frac{(1+x)}{(1+1/c)+x}[/tex]
Let C = 1 + 1/c
[tex]y=\frac{(1+x)}{C+x}[/tex]
Chet
 
can we straight sub C =1 + 1/c ? the c is the question not the original c (constant ) from the integrate( (dx/X+1)) ? dx ?
 
delsoo said:
can we straight sub C =1 + 1/c ? the c is the question not the original c (constant ) from the integrate( (dx/X+1)) ? dx ?

Of course.

Chet
 
the c is the question the original c (constant ) from the integral ( (dx/X+1)) ? dx ? am i right?
 
delsoo said:
the c is the question the original c (constant ) from the integral ( (dx/X+1)) ? dx ? am i right?
In your original solution, the choice of adding ln c as the constant of integration was not unique. You could just as easily have added a different constant, say c' (i.e., without the natural log), without affecting the correctness of the solution.

Chet