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    In a pond the amount of pondeweed {P} grows at a rate proportional to the amount of pondweed already present in the pond. Pondweed is also removed by fish eating it at a constant rate of Q per unit of time.

    Write a DE relating P and t.

    So I have dP/dT = kP.

    But where to go from the last part is it:

    Q=dp/dt ?
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    How about dP/dT = kp - Q ?
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    (Original post by Mihael_Keehl)
    In a pond the amount of pondeweed {P} grows at a rate proportional to the amount of pondweed already present in the pond. Pondweed is also removed by fish eating it at a constant rate of Q per unit of time.

    Write a DE relating P and t.

    So I have dP/dT = kP.

    But where to go from the last part is it:

    Q=dp/dt ?
    Nah, it's \frac{dP}{dt} = kP - Q
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    (Original post by khaleesi98)
    How about dP/dT = kp - Q ?
    (Original post by Zacken)
    Nah, it's \frac{dP}{dt} = kP - Q
    So then Q is just a constant for which the population is decreasing by?
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    (Original post by Mihael_Keehl)
    So then Q is just a constant for which the population is decreasing by?
    Yes.
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    (Original post by Mihael_Keehl)
    So then Q is just a constant for which the population is decreasing by?
    Yes exactly ☺️
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    (Original post by Zacken)
    Yes.
    (Original post by khaleesi98)
    Yes exactly ☺️
    thnx
 
 
 
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