How Does the Initial Condition y(0)=1 Affect the Solution to dy/dx=(y-1)^2?

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SUMMARY

The differential equation dy/dx = (y-1)^2 with the initial condition y(0) = 1 leads to a unique situation where no value of the constant c can satisfy the condition. The separation of variables method yields the solution y = 1 - 1/(x+c), but substituting x = 0 results in a contradiction. The discussion concludes that y = 1 is a fixed point, indicating that all solutions either approach or diverge from this line, emphasizing the stability of the fixed point in the context of differential equations.

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dy/dx = (y-1)^2 given the initial condition y(0) =1 find an explicit solution.


separation of variables gives:

(y-1)^-2 dy = dx

integrating both sides I get

-(y-1)^-1 = x + c

-1= (y-1)(x+c)

-1/(x+c) = y - 1

y= 1 - 1/(x+c) but how can the intial condition work?

no value of c will make 1= 1 - 1(0+c)
 
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Pretty sure y = 1 is a fixed point (or a collection thereof, the whole y = 1 line) so you can't have any solution involving that condition since all solutions are basically just integral curves. Therefore all solutions/integral curves will either approach the y = 1 line or go away from it depending on its stability.
 

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