iRaid
- 558
- 8
Homework Statement
\frac{dx}{dt}=x-x^{2}
Homework Equations
The Attempt at a Solution
I think the only thing I have wrong so far is how to finish it because I can't find anything wrong with my work, but I don't know how the book gets their final answer.
Separate variables...
\int \frac{dx}{x(1-x)}=\int dt
Partial fraction decomposition..
\int (\frac{1}{x}-\frac{1}{x-1})dx=t+C\\ln|x|-ln|x-1|=t+C\\ln|\frac{x}{x-1}|=t+C
Using properties of e...
\frac{x}{x-1}=e^{t}e^{C}
D=e^C (professor wants us to write it like this) and multiply by x-1 on both sides..
x=De^{t}(x-1)
That's not the solution though and I'm not sure why.
Final answer: x(t)=\frac{C}{C-e^{t}}