(adsbygoogle = window.adsbygoogle || []).push({}); A logistic function has formula U(n+1)=rUn

This models the growth in the fish population from year n to year n+1. If you now decided to harvest H fish, your equation looks like this: U(n+1)=rUn-H

Now, they want me to find the maximum H for which the population stays constant (growth factor r=1). Ie., if H is too large the population dies out!

2. Relevant equations

The exact equation is U(n+1)=[(-1x10^-5)(Un^2)+1.6Un]-H

3. The attempt at a solution

Somehow I need to solve for H and then look at the formula as a quadratic, look at the discriminant and then solve for H....

I think H needs to replace some variable in the equation...

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# Mathematical modelling - Fishery - Harvest equation

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