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Differential Equations

dP/dt=kP((10^6)-P). In the last 10 years the pop has grown from 100,000 to 400,000.
Determine k? k>0
(A step by step method will be really helpful, I have past the process of intergrating both sides and have solved the partial fractions).
Reply 1
Original post by Engineeringbeast
dP/dt=kP((10^6)-P). In the last 10 years the pop has grown from 100,000 to 400,000.
Determine k? k>0
(A step by step method will be really helpful, I have past the process of intergrating both sides and have solved the partial fractions).


People will be more likely to help if you post what you've done.
Original post by BabyMaths
People will be more likely to help if you post what you've done.


And post in LaTeX.
Reply 3
Engineeringbeast you really have to get used to Latex; this question doesn't need it much but some old questions you've had aren't understandable unless you use it haha. Here's a link for reference: http://www.thestudentroom.co.uk/wiki/latex

This is the question in Latex (well at least I hope it is):

dPdt=kP(106P)\frac{dP}{dt} = {kP(10^6-P)}

You should just get:

k dt=1P(106P) dP\int k\ dt = \int \frac{1}{P(10^6-P)}\ dP

Once you've solved it, you just sub in your P value of 100,000 at t = 0 (as that's the initial population) to get the constant integer, then sub in your P value of 400,000 at t = 10. This is assuming t is measured in years and P is measured per person.

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