Aswar Anas and Marsidi Michaelis-Menten Models with Constant Harvesting of Restricted Prey Populations Minimum Place and Amount Capacity CONTACT: Marsidi, marsidiarin@gmail.com Departement of Mathematics Education Universitas PGRI Argopuro Jember, Jember, Jawa Timur 68121, Indonesia The article can be accessed here. https://doi.org/10.15642/mantik.2021.7.2.107-114 Michaelis-Menten Models with Constant Harvesting of Restricted Prey Populations Minimum Place and Amount Capacity Aswar Anas1, Marsidi2* 1,2Department of Mathematics Education, Universitas PGRI Argopuro, Jember, Indonesia Article history: Received Jun 16, 2021 Revised, Jul 14, 2021 Accepted, Oct 31, 2021 Kata Kunci: Model rantai makanan, Model Michaelis-Menten, Model mangsa dan pemangsa Abstrak. Pemodelan rantai makanan saat ini sedang berkembang pesat. Ekosistem terlindungi dari rantai proses makan dan memakan. Semua makhluk hidup saling membutuhkan, namun jika proses memakannya tidak seimbang, maka kepunahan makhluk hidup akan terjadi. Salah satunya adalah model mangsa dan pemangsa yang berfungsi sebagai penyeimbang dalam sistem rantai makanan. Model Michaelis-Menten merupakan model mangsa- pemangsa yang pada intinya menjaga kepunahan mangsa. Permasalahannya adalah bagaimana menjaga mangsa tidak punah namun dengan pemanenan maksimal di suatu tempat dan jumlah minimum mangsa dengan waktu yang tepat. Metode yang digunakan untuk mengatasi masalah tersebut adalah menambah dua variabel baru pada model Michaelis-Menten, yaitu jumlah minimum mangsa dan kapasitas tempat yang akan ditempati. Terlihat bahwa sistem akan berada dalam keseimbangan jika tingkat kematian pemangsa besar, sehingga mangsa terjaga dari kepunahan sampai pemanenan. Selain itu waktu yang tepat untuk perkembangbiakan yang baik juga dapat ditentukan. Dari model ini didapatkan waktu yang tepat untuk pemanenan agar tidak terjadi kepunahan mangsa adalah β„Ž = 𝑛( 𝐾2βˆ’π‘š2 4 𝐾 ). Keywords: Food chain model, Mich- aelis-Menten model, Prey-predator model Abstract. Food chain modeling is currently developing rapidly. The ecosystem is protected from the chain of eating and eating pro- cesses. All living things need each other, but if the process of eating them is not balanced, then the extinction of living things will occur. One of them is the prey and predator model that serves as a balancer in the food chain system. The Michaelis-Menten model is a prey- predator model that essentially prevents prey extinction. The prob- lem is how to keep the prey from becoming extinct but with maxi- mum harvesting in one place and the minimum amount of prey at the right time. The method used to overcome this problem is to add two new variables to the Michaelis-Menten model, namely the min- imum number of prey and the capacity of the place to be occupied. It is seen that the system will be in equilibrium if the predator mor- tality rate is large so that the prey is kept from extinction until har- vesting. In addition, the right time for good breeding can also be determined. From this model, it is found that the right time for har- vesting so that prey extinction does not occur is β„Ž = 𝑛( 𝐾2βˆ’π‘š2 4 𝐾 ). How to cite: A. Anas and Marsidi, β€œMichaelis-Menten Models with Constant Harvesting of Restricted Prey Populations Minimum Place and Amount Capacity”, J. Mat. Mantik, vol. 7, no. 2, pp. 107-114, October 2021. Jurnal Matematika MANTIK Vol. 7, No. 2, October 2021, pp. 107-114 ISSN: 2527-3159 (print) 2527-3167 (online) mailto:marsidiarin@gmail.com http://u.lipi.go.id/1458103791 Jurnal Matematika MANTIK Vol 7, No 2, October 2021, pp. 107-114 108 1. Introduction The food chain is a system created in nature. The dependence of living things on other living things is a normal interaction on this earth. This interaction occurs because of the needs of one party or two parties. The relationship between prey and predators is a one- sided relationship that harms one party, this is very closely related because predators can only survive if there is prey. As a result, the chances of predators experiencing extinction are small. In addition, the predator also functions as a controller of the growth rate of the prey [1]. Dongmei et al. stated that population extinction occurred because the initial population was too low [2]. If this happens, the prey population will be decrease and extinction may occur. As a result, predator populations are increasingly threatened indirectly. With the extinction of the Prey, the Predator also experiences extinction. The prey in this model is harvested while the predator population is not harvested because it has no commercial value. They are states that the commercial value is determined by the maximum value of h because if the prey harvested exceeds the value of h, the prey will become extinct. The cause of the extinction of the Prey is also influenced by over-harvesting. There- fore, it is necessary to limit the number of prey so that the number of prey remains under control and does not exceed the existing capacity [3] . The Lotka–Volterra model is frequently used to describe the dynamics of ecological systems in which two species interact, one a predator and one its prey. The model is sim- plified with the following assumptions: (1) only two species exist: fox and rabbit; (2) rab- bits are born and then die through predation or inherent death; (3) foxes are born and their birth rate is positively affected by the rate of predation, and they die naturally [4]. The Michaelis-Menten model is a predator-prey model which is a generalization of the Lotka- Volterra model [5]. This model is used for events if the interaction system between indi- viduals in a population has limited capacity. However, in this case, harvesting is also ap- plied. Previously, researchers researched the Lotka-Volterra Proportional Predation and Prey model on the Von Bertallanfy [6] logistics modifications model . In this model, the researcher concludes that the number of predators in a place is highly dependent on the initial number of prey, the birth rate of the predator, and the birth rate of the prey. If the initial number of prey is large and the birth rate of prey is also large, the growth rate of predators increases. And if the birth constant of predators is small and the number of pred- ators is smaller than the prey, there will be a decrease in the growth rate of prey. From previous research, researchers are interested in researching the Michaelis-Menten model, because this model prevents the extinction of both prey and predators. However, the re- searchers added the variables of space capacity and the minimum amount of prey that must be given. 2. Research Method This research method is a literature study of the addition of the [7] variable with the capacity of the place and the minimum number of prey, the equation comes from: According to [7], the equation for population growth and space capacity is formed by the formula: 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 ) (1) From [8] with the addition of the assumption that the minimum number of population also affects the rate of population growth, then the form is: 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )(1βˆ’ π‘š 𝑃(𝑑) ) (2) Aswar Anas and Marsidi Michaelis-Menten Models with Constant Harvesting of Restricted Prey Populations Minimum Place and Amount Capacity 109 where n is the coefficient of the growth rate of the prey population, P(t) is the number of prey populations at t, K is the capacity of the place, and m is the minimum number of populations. Equation (2) is a logistic model that is influenced by the capacity of the place and the minimum number population. If the growth rate is also affected by the number of harvests of h, then equation (2) changes to: 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )(1βˆ’ π‘š 𝑃(𝑑) )βˆ’β„Ž (3) Where 0 ≀ β„Ž ≀ β„Žπ‘šπ‘Žπ‘₯, h is the prey harvest rate constant and is the maximum harvested prey. Xiao, et al describe the general formula for the persistence model in prey as follows [9]: 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )βˆ’ 𝑐𝑃(𝑑)𝑦(𝑑) π‘Ÿπ‘¦(𝑑)+𝑃(𝑑) βˆ’β„Ž 𝑑𝑦(𝑑) 𝑑𝑑 = 𝑦(𝑑)(βˆ’π· + 𝑓𝑃(𝑑) π‘Ÿπ‘¦(𝑑)+𝑃(𝑑) ) (4) where π‘Ÿ is the satisfaction level of the Predator, 𝑐 the number of prey captured, f the cconversion factor between the number of predators born for each prey captured, 𝐷 is the mortality rate of the predator. By adding the factor of the minimum number of prey population to reproduce, it is obtained 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )(1βˆ’ π‘š 𝑃(𝑑) )βˆ’ 𝑐𝑃(𝑑)𝑦(𝑑) π‘Ÿπ‘¦(𝑑)+𝑃(𝑑) βˆ’β„Ž 𝑑𝑦(𝑑) 𝑑𝑑 = 𝑦(𝑑)(βˆ’π· + 𝑓𝑃(𝑑) π‘Ÿπ‘¦(𝑑)+𝑃(𝑑) ) (5) By [10] Equation (5) is sought a solution so that the prey does not experience extinction with: a. Look for the maximum harvest value if predator is not present. b. Search for fixed points. c. Analysis of system stability at points 𝑇1 and 𝑇2. 3. Discussion The following will discuss certain limits of harvesting a population to prevent extinc- tion, then look for a fixed point from the Michaelis-Menten model to analyze the stability of the system at each of these fixed points and also perform simulations with different parameters. 3.1. Finding of Harvesting Maximum Value (π’‰π’Žπ’‚π’™) Without Predator Condition In equation (2) we have maximum points if: 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )(1βˆ’ π‘š 𝑃(𝑑) ) = 0 (6) By [11] with a condition half of the carrying capacity and the minimum number of prey population 𝑃(𝑑). In this case, fixed point occurs in 𝑃(𝑑) = π‘š and 𝑃(𝑑) = 𝐾. If 𝑃(𝑑) = π‘š then this point is not stable. It is caused by the population 𝑃(𝑑) > π‘š. It means that the population will grow rapidly and avoid the 𝑃(𝑑) = π‘š and will attain 𝑃(𝑑) = 𝐾. Let π‘š ≀ 𝑃0 < ( 𝐾+π‘š 2 ), point 𝑃0 moves rapidly towards the maximum point when 𝑃0 = ( 𝐾+π‘š 2 ). Jurnal Matematika MANTIK Vol 7, No 2, October 2021, pp. 107-114 110 Whereas if ( 𝐾+π‘š 2 ) < 𝑃0 ≀ 𝐾, then this point moves slowly towards the stable point by K. If 0 ≀ 𝑃0 < π‘š, then the population will be moving down so that the population experiences extinction. While if 𝐾 < 𝑃0 , then this point will be moving slowly down to stable point K. Since harvesting results must be maximum, then the predator must be eliminated or equal to zero and 𝑃(𝑑) = 𝐾+π‘š 2 , such that we have 𝑑𝑃(𝑑) 𝑑𝑑 = 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )(1βˆ’ π‘š 𝑃(𝑑) )βˆ’β„Ž = 0 ⟹ 𝑛𝑃(𝑑)(1βˆ’ 𝑃(𝑑) 𝐾 )(1βˆ’ π‘š 𝑃(𝑑) ) = β„Ž ⟹ 𝑛(πΎβˆ’π‘ƒ(𝑑))(𝑃(𝑑)βˆ’π‘š) 𝐾 = β„Ž ; 𝑃(𝑑) = 𝐾+π‘š 2 So that: 𝑛( 𝐾+π‘š 2 )(1βˆ’ 𝐾+π‘š 2𝐾 )(1βˆ’ 2π‘š (𝐾+π‘š) ) = β„Ž ⟹ 𝑛( 𝐾+π‘š 2 )( 2πΎβˆ’πΎ+π‘š 2𝐾 )( 𝐾+π‘šβˆ’2π‘š 𝐾+π‘š ) = β„Ž ⟹ 1 2 𝑛( 𝐾+π‘š 2𝐾 )(𝐾 βˆ’π‘š) = β„Ž ⟹ 𝑛( 𝐾2βˆ’π‘š2 4𝐾 ) = β„Ž Therefore, the maximum harvesting is bounded by β„Ž = 𝑛( 𝐾2βˆ’π‘š2 4𝐾 ). 3.2. Finding Fixed Point Let 𝑓1(𝑃,𝑦) = 𝑛𝑝(1βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’ 𝑐𝑃𝑦 π‘Ÿπ‘¦+𝑃 βˆ’β„Ž 𝑓2(𝑃,𝑦) = 𝑦(βˆ’π· + 𝑓𝑝 π‘Ÿπ‘¦+𝑃 ) (7) Suppose 𝑓1(𝑃,𝑦) = 0; 𝑓2(𝑃,𝑦) = 0 such that we have 𝑦 = 0 or (βˆ’π· + 𝑓𝑝 π‘Ÿπ‘¦+𝑃 ) = 0. (βˆ’π· + 𝑓𝑝 π‘Ÿπ‘¦+𝑃 ) = 0 ⟺ 𝑓𝑝 π‘Ÿπ‘¦+𝑃 = 𝐷 ⟺ 𝑓𝑃 = π·π‘Ÿπ‘¦ +𝑃𝐷 ⟺ π‘“π‘ƒβˆ’π‘ƒπ· π·π‘Ÿ = 𝑦 Then we have 𝑦1 = 0; 𝑦2 = 𝑃(π‘“βˆ’π·) π·π‘Ÿ . Furthermore, finding the points 𝑃1 and 𝑃2 by substituting 𝑦1 = 0 to 𝑓1(𝑃,𝑦1) = 0. 𝑓1(𝑃,𝑦) = 𝑛𝑝(1βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’ 𝑐𝑃0 π‘Ÿ0+𝑃 βˆ’β„Ž = 0 ⟺ 𝑛𝑝(1βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’β„Ž = 0 Aswar Anas and Marsidi Michaelis-Menten Models with Constant Harvesting of Restricted Prey Populations Minimum Place and Amount Capacity 111 ⟺ 𝑛𝑝( πΎβˆ’π‘ƒ 𝐾 )( π‘βˆ’π‘š 𝑃 )βˆ’β„Ž = 0 ⟺ 𝑛 𝐾 (𝐾𝑃 βˆ’πΎπ‘š +π‘ƒπ‘šβˆ’π‘ƒ2)βˆ’β„Ž = 0 ⟺ 𝑛𝑃 βˆ’π‘›π‘š + 𝑃 𝐾 π‘šπ‘› βˆ’ 𝑛 𝐾 𝑃2 βˆ’β„Ž = 0 ⇔ βˆ’ 𝑛 𝐾 𝑃2 +𝑃(𝑛 + π‘šπ‘› 𝐾 )βˆ’(β„Ž +π‘›π‘š) = 0 ⇔ 𝑛 𝐾 𝑃2 βˆ’(𝑛 + π‘šπ‘› 𝐾 )𝑃 +(β„Ž +π‘›π‘š) = 0 Such that 𝑃1,2 = (𝑛+ π‘šπ‘› 𝐾 )±√(βˆ’(𝑛+ π‘šπ‘› 𝐾 )) 2 βˆ’4( 𝑛 𝐾 )(β„Ž+π‘›π‘š) 2( 𝑛 𝐾 ) 𝑃1,2 = (𝑛+ π‘šπ‘› 𝐾 )±√(𝑛+ π‘šπ‘› 𝐾 ) 2 βˆ’4( 𝑛 𝐾 )(β„Ž+π‘›π‘š) 2( 𝑛 𝐾 ) For 𝑦2 = 𝑃(π‘“βˆ’π·) π·π‘Ÿ we have 𝑛𝑝(1βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’( 𝑐𝑃 𝑃(π‘“βˆ’π·) π·π‘Ÿ π‘Ÿ 𝑃(π‘“βˆ’π·) π·π‘Ÿ +𝑃 )βˆ’β„Ž = 0 ⇔ 𝑛𝑝(1 βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’( 𝑐𝑃 𝑃(π‘“βˆ’π·) π·π‘Ÿ π‘Ÿ 𝑃(π‘“βˆ’π·)+π‘ƒπ·π‘Ÿ π·π‘Ÿ )βˆ’β„Ž = 0 ⇔ 𝑛𝑝(1 βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’ (𝑐𝑃2π‘“βˆ’π‘π‘ƒ2𝐷) π‘Ÿπ‘ƒπ‘“βˆ’π‘ƒπ·π‘Ÿ+π‘ƒπ·π‘Ÿ βˆ’β„Ž = 0 ⇔ 𝑛𝑝(1 βˆ’ 𝑃 𝐾 )(1βˆ’ π‘š 𝑃 )βˆ’ (𝑐𝑃2π‘“βˆ’π‘π‘ƒ2𝐷) π‘Ÿπ‘ƒπ‘“ βˆ’β„Ž = 0 ⇔ 𝑛 𝐾 (𝐾𝑃 βˆ’πΎπ‘š +π‘ƒπ‘šβˆ’π‘ƒ2)βˆ’ (𝑐𝑃2π‘“βˆ’π‘π‘ƒ2𝐷) π‘Ÿπ‘ƒπ‘“ βˆ’β„Ž = 0 ⇔ π‘Ÿπ‘ƒπ‘“π‘› 𝐾 (𝐾𝑃 βˆ’πΎπ‘š +π‘ƒπ‘š βˆ’π‘ƒ2)βˆ’(𝑐𝑃2𝑓 βˆ’π‘π‘ƒ2𝐷)βˆ’β„Žπ‘Ÿπ‘ƒπ‘“ = 0 ⇔ 𝑃( π‘Ÿπ‘“π‘› 𝐾 (𝐾𝑃 βˆ’πΎπ‘š +π‘ƒπ‘šβˆ’π‘ƒ2)βˆ’(𝑐𝑃𝑓 βˆ’π‘π‘ƒπ·)βˆ’β„Žπ‘Ÿπ‘“) = 0 ⇔ 𝑃((π‘Ÿπ‘“π‘›π‘ƒ βˆ’π‘Ÿπ‘“π‘›π‘š + π‘Ÿπ‘“π‘›π‘ƒπ‘š 𝐾 βˆ’ π‘Ÿπ‘“π‘›π‘ƒ2 𝐾 )βˆ’π‘π‘ƒπ‘“ +𝑐𝑃𝐷 = β„Žπ‘Ÿπ‘“) = 0 ⇔ 𝑃(βˆ’ π‘Ÿπ‘“π‘› 𝐾 𝑃2 +𝑃(π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“ +𝑐𝐷)βˆ’(β„Žπ‘Ÿπ‘“ +π‘Ÿπ‘›π‘“π‘š)) = 0 ⇔ 𝑃( π‘Ÿπ‘“π‘› 𝐾 𝑃2 βˆ’(π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“ +𝑐𝐷)𝑃 +(β„Žπ‘Ÿπ‘“ +π‘Ÿπ‘›π‘“π‘š)) = 0 Thus 𝑃 = 0 or 𝑃1,2 = (π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“+𝑐𝐷)±√(βˆ’(π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“+𝑐𝐷)) 2 βˆ’4( π‘Ÿπ‘“π‘› 𝐾 )(β„Žπ‘Ÿπ‘“+π‘Ÿπ‘›π‘“π‘š) 2( π‘Ÿπ‘“π‘› 𝐾 ) 𝑃1,2 = (π‘Ÿπ‘“π‘› (𝐾+π‘š) 𝐾 βˆ’π‘π‘“+𝑐𝐷)±√(π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“+𝑐𝐷) 2 βˆ’4( π‘Ÿπ‘“π‘› 𝐾 )(β„Žπ‘Ÿπ‘“+π‘Ÿπ‘›π‘“π‘š) 2( π‘Ÿπ‘“π‘› 𝐾 ) It is impossible for 𝑃 = 0. Since this model must have a minimum amount so that the prey can grow. From the results above, we have a fixed points as follows: Jurnal Matematika MANTIK Vol 7, No 2, October 2021, pp. 107-114 112 𝑇1:(𝑃1,𝑦1) = ( (𝑛+ π‘šπ‘› 𝐾 )+√((𝑛+ π‘šπ‘› 𝐾 )) 2 βˆ’4( 𝑛 𝐾 )(β„Ž+π‘›π‘š) 2( 𝑛 𝐾 ) ,0 ) 𝑇2:(𝑃2,𝑦1) = ( (𝑛+ π‘šπ‘› 𝐾 )βˆ’βˆš(𝑛+ π‘šπ‘› 𝐾 ) 2 βˆ’4( 𝑛 𝐾 )(β„Ž+π‘›π‘š) 2( 𝑛 𝐾 ) ,0) 𝑇3:(𝑃1 βˆ—,𝑦2 βˆ—) = ( (π‘Ÿπ‘“π‘› (𝐾+π‘š) 𝐾 βˆ’π‘π‘“+𝑐𝐷)+√(π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“+𝑐𝐷) 2 βˆ’4( π‘Ÿπ‘“π‘› 𝐾 )(β„Žπ‘Ÿπ‘“+π‘Ÿπ‘›π‘“π‘š) 2( π‘Ÿπ‘“π‘› 𝐾 ) , 𝑃1 βˆ—(π‘“βˆ’π·) π·π‘Ÿ ) 𝑇4:(𝑃2 βˆ—,𝑦2 βˆ—) = ( (π‘Ÿπ‘“π‘› (𝐾+π‘š) 𝐾 βˆ’π‘π‘“+𝑐𝐷)βˆ’βˆš(π‘Ÿπ‘“π‘›+ π‘Ÿπ‘“π‘›π‘š 𝐾 βˆ’π‘π‘“+𝑐𝐷) 2 βˆ’4( π‘Ÿπ‘“π‘› 𝐾 )(β„Žπ‘Ÿπ‘“+π‘Ÿπ‘›π‘“π‘š) 2( π‘Ÿπ‘“π‘› 𝐾 ) , 𝑃2 βˆ—(π‘“βˆ’π·) π·π‘Ÿ ) Equilibrium analysis is carried out to find out the points that cause the system to be in equilibrium and not, to analyze it, look for real eigenvalues at each equilibrium point [12]. To find the stability of the equilibrium point of a model, you can use the Jacobian matrix with the order 2Γ—2. This matrix is discussed in the next sub-chapter. 3.3. Jacobian Matrix In [13] let the equation system equation (5) written by: 𝑑𝑃 𝑑𝑑 = 𝑓1(𝑃,𝑦) π‘‘π‘Œ 𝑑𝑑 = 𝑓2(𝑃,𝑦) Such that, the Jacobian matrix can be formed by: 𝐽 = [ πœ•π‘“1 πœ•π‘ƒ πœ•π‘“1 πœ•π‘¦ πœ•π‘“2 𝑃 πœ•π‘“2 πœ•π‘¦ ] 𝐽 = [ βˆ’ 2𝑛𝑝 𝐾 + 𝑛(𝐾+π‘š) 𝐾 βˆ’ π‘Ÿπ‘π‘¦2+𝑐𝑦𝑃+π‘Ÿπ‘π‘ƒπ‘¦2 (π‘Ÿπ‘¦+𝑃)2 βˆ’ 𝑐𝑃2 (π‘Ÿπ‘¦+𝑃)2 π‘“π‘Ÿπ‘¦2 (π‘Ÿπ‘¦+𝑃)2 βˆ’π· + π‘“π‘Ÿπ‘¦2+π‘“π‘¦π‘ƒβˆ’π‘“π‘ƒπ‘¦π‘Ÿ (π‘Ÿπ‘¦+𝑃)2 ] The stability of the system of equations (5) will be known by analyzing the eigen values of the Jacobian matrix. 3.4. Fixed Point Stable Analysis The following discussion discusses the stability analysis of fixed points using the Ja- cobi matrix of order 2Γ—2 and only discussed in point 𝑇1(𝑃1,𝑦1), 𝑇2(𝑃2,𝑦1). 3.4.1 Stable system at fixed point π‘»πŸ By [14] we take the fixed point Aswar Anas and Marsidi Michaelis-Menten Models with Constant Harvesting of Restricted Prey Populations Minimum Place and Amount Capacity 113 𝑇1:(𝑃1,𝑦1) = ( (𝑛+ π‘šπ‘› 𝐾 )+√(𝑛+ π‘šπ‘› 𝐾 ) 2 βˆ’4( 𝑛 𝐾 )(β„Ž+π‘›π‘š) 2( 𝑛 𝐾 ) ,0). We substitute the point 𝑇1 to Jacobian Matrix as follows. 𝐽1 = [ βˆ’ 2𝑛𝑝 𝐾 + 𝑛(𝐾+π‘š) 𝐾 βˆ’ π‘Ÿπ‘π‘¦2+𝑐𝑦𝑃+π‘Ÿπ‘π‘ƒπ‘¦2 (π‘Ÿπ‘¦+𝑃)2 βˆ’ 𝑐𝑃2 (π‘Ÿπ‘¦+𝑃)2 π‘“π‘Ÿπ‘¦2 (π‘Ÿπ‘¦+𝑃)2 βˆ’π· + π‘“π‘Ÿπ‘¦2+π‘“π‘¦π‘ƒβˆ’π‘“π‘ƒπ‘¦π‘Ÿ (π‘Ÿπ‘¦+𝑃)2 ] Then we have: 𝐽1 = [ βˆ’ 2𝑛𝑝 𝐾 + 𝑛(𝐾+π‘š) 𝐾 βˆ’ π‘Ÿπ‘0+𝑐0𝑃+π‘Ÿπ‘π‘ƒ0 (π‘Ÿ0+𝑃)2 βˆ’ 𝑐𝑃2 (π‘Ÿ0+𝑃)2 0 βˆ’π· ] 𝐽1 = [ βˆ’ 2𝑛𝑝 𝐾 + 𝑛(𝐾+π‘š) 𝐾 βˆ’π‘ 0 βˆ’π· ] 𝐽1 = [ βˆ’π‘› βˆ’ π‘šπ‘› 𝐾 βˆ’βˆš(𝑛 + π‘šπ‘› 𝐾 )βˆ’ 4𝑛(π‘šπ‘›+β„Ž) 𝐾 + 𝑛(𝐾+π‘š) π‘š βˆ’π‘ 0 βˆ’π· ] 𝐽1 = [ βˆ’βˆš(𝑛 + π‘šπ‘› 𝐾 ) 2 βˆ’ 4𝑛(π‘šπ‘›+β„Ž) 𝐾 βˆ’π‘ 0 βˆ’π· ] The eigen value can be obtained by 𝑑𝑒𝑑(π΄βˆ’πœ†1𝐼) = 0. (βˆ’βˆš(𝑛+ π‘šπ‘› 𝐾 ) 2 βˆ’ 4𝑛(π‘šπ‘›+β„Ž) 𝐾 βˆ’πœ†)(βˆ’π· βˆ’πœ†) = 0 ⇔ πœ†1 = βˆ’βˆš(𝑛 + π‘šπ‘› 𝐾 ) 2 βˆ’ 4𝑛(π‘šπ‘›+β„Ž) 𝐾 or πœ†2 = βˆ’π· with β„Ž = 𝑛( 𝐾2βˆ’π‘š2 4𝐾 ) we have πœ†1 = βˆ’βˆš2βˆšβˆ’ 𝑛2π‘š(πΎβˆ’π‘š) 𝐾2 or πœ†2 = βˆ’π·. From the equation above we know that πœ†1 is not real eigen value because 𝑛,π‘š,𝐾 is a pos- itive parameter with 𝐾 > π‘š and πœ†2 ≀ 0 if 𝐷 is a positive integer. It show that 𝑇1 is stable. 3.4.2 Stable system at fixed point π‘»πŸ Let 𝑇2:(𝑃2,𝑦1) = ( (𝑛+ π‘šπ‘› 𝐾 )βˆ’βˆš(𝑛+ π‘šπ‘› 𝐾 ) 2 βˆ’4( 𝑛 𝐾 )(β„Ž+π‘›π‘š) 2( 𝑛 𝐾 ) ,0). With the same way we obtain that πœ†1 = √(𝑛 + π‘šπ‘› 𝐾 ) 2 βˆ’ 4𝑛(π‘šπ‘›+β„Ž) 𝐾 or πœ†2 = βˆ’π·. Wit β„Ž = 𝑛( 𝐾2βˆ’π‘š2 4𝐾 ) we get πœ†1 = √2βˆšβˆ’ 𝑛2π‘š(πΎβˆ’π‘š) 𝐾2 or πœ†2 = βˆ’π·, because πœ†1 is not real eigen value and πœ†2 ≀ 0 if 𝐷 is a positive integer. It show that 𝑇2 is stable [15]. Jurnal Matematika MANTIK Vol 7, No 2, October 2021, pp. 107-114 114 4. Conclusion From the calculation results obtained 4 fixed points. In here we are only discussing points that are 𝑇1and 𝑇2. 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