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**Cotty** Thanks for giving me a hand! So isn't the integral of 1/(1-x) = -ln(1-x), by using substitution? I think i might have arrived at the solution with it being:

x(t) = Ae^rt/ (1+Ae^(rt)) where A=e^c

And with your first answer, how can i show that the derivative is positive though if x is a function of t, but instead of it actually being in terms of t its just written as x(t), meaning that we don't actually know that when t is positive that x(t) is positive? Ie. if x(t)=1000-t, for all t<1000, won't the derivate be negative?

Also how do you write with the integrals and everything? People always answer my questions so neatly and mine is just a mess trying to write without the maths stuff!! haha