Integrability and Multiple Limit Cycles in a Predator-Prey System with Fear Effect

<p>The phase plane of system (<a href="https://static.hindawi.com/articles/jfs/volume-2019/3948621/figures/#EEq3.9">42</a>) when <span class="nowrap"><svg height="12.7178pt" id="M67" style="vertical-align:-3.42947pt" version="1.1" viewbox="-0.0498162 -9.28833 153.824 12.7178" width="153.824pt" xmlns="http://www.w3.org/2000/svg"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M545 106L524 126C493 85 467 65 455 65C438 65 427 113 405 238C448 295 498 362 543 439L533 448L478 435C453 386 423 331 398 295H395C370 404 347 448 282 448C169 448 23 309 23 153C23 54 65 -12 128 -12C203 -12 283 70 339 155H341C360 29 380 -12 411 -12C444 -12 491 11 545 106ZM333 204C265 95 210 54 169 54C137 54 113 96 113 171C113 302 191 405 252 405C301 405 318 306 333 204Z"></path></g><g transform="matrix(.013,0,0,-0.013,11.017,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,22.28,0)"><path d="M558 587C558 666 497 712 432 712C379 712 330 691 284 650C212 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Journal of Function Spaces

fig1

Figure 1

Figure 1: Integrability and Multiple Limit Cycles in a Predator-Prey System with Fear Effect 