Consider the autonomus equation $frac{dy}{dt}=-2(y-1)(y-2)(y-a)^2$












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$begingroup$


Consider the autonomus equation $frac{dy}{dt}=-2(y-1)(y-2)(y-a)^2$, where $a$ is any real number.



Then,



$(1)$ Plot the phase diagram showing the solution curves.



$(2)$ show that new solution can be generated from the old solutions (in $(a)$) by time shifting i.e, replacing $y(t)$ by $y(t-t_0)$.



Answer:



$(a)$ I have drawn the phase plot showing the solutions.



Please help me with the part $(b)$.



If we replace $y(t)$ by $y(t-t_0)$, then we have



$frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$.



How to confirm that we get a new solution?



Help me



$










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    0












    $begingroup$


    Consider the autonomus equation $frac{dy}{dt}=-2(y-1)(y-2)(y-a)^2$, where $a$ is any real number.



    Then,



    $(1)$ Plot the phase diagram showing the solution curves.



    $(2)$ show that new solution can be generated from the old solutions (in $(a)$) by time shifting i.e, replacing $y(t)$ by $y(t-t_0)$.



    Answer:



    $(a)$ I have drawn the phase plot showing the solutions.



    Please help me with the part $(b)$.



    If we replace $y(t)$ by $y(t-t_0)$, then we have



    $frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$.



    How to confirm that we get a new solution?



    Help me



    $










    share|cite|improve this question









    $endgroup$















      0












      0








      0


      2



      $begingroup$


      Consider the autonomus equation $frac{dy}{dt}=-2(y-1)(y-2)(y-a)^2$, where $a$ is any real number.



      Then,



      $(1)$ Plot the phase diagram showing the solution curves.



      $(2)$ show that new solution can be generated from the old solutions (in $(a)$) by time shifting i.e, replacing $y(t)$ by $y(t-t_0)$.



      Answer:



      $(a)$ I have drawn the phase plot showing the solutions.



      Please help me with the part $(b)$.



      If we replace $y(t)$ by $y(t-t_0)$, then we have



      $frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$.



      How to confirm that we get a new solution?



      Help me



      $










      share|cite|improve this question









      $endgroup$




      Consider the autonomus equation $frac{dy}{dt}=-2(y-1)(y-2)(y-a)^2$, where $a$ is any real number.



      Then,



      $(1)$ Plot the phase diagram showing the solution curves.



      $(2)$ show that new solution can be generated from the old solutions (in $(a)$) by time shifting i.e, replacing $y(t)$ by $y(t-t_0)$.



      Answer:



      $(a)$ I have drawn the phase plot showing the solutions.



      Please help me with the part $(b)$.



      If we replace $y(t)$ by $y(t-t_0)$, then we have



      $frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$.



      How to confirm that we get a new solution?



      Help me



      $







      ordinary-differential-equations






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      asked Jan 14 at 10:38









      M. A. SARKARM. A. SARKAR

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          $begingroup$

          $$frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$$
          Change of variable : $quadtheta=t-t_0$ :
          $$frac{dy(theta)}{dt}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
          $dtheta=dt$
          $$frac{dy(theta)}{dtheta}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
          Thus $y(theta)$ is solution of the ODE.



          Since $y(theta)=y(t-t_0)$ this proves that $y(t-t_0)$ is also solution.






          share|cite|improve this answer









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            $begingroup$

            $$frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$$
            Change of variable : $quadtheta=t-t_0$ :
            $$frac{dy(theta)}{dt}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
            $dtheta=dt$
            $$frac{dy(theta)}{dtheta}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
            Thus $y(theta)$ is solution of the ODE.



            Since $y(theta)=y(t-t_0)$ this proves that $y(t-t_0)$ is also solution.






            share|cite|improve this answer









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              $begingroup$

              $$frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$$
              Change of variable : $quadtheta=t-t_0$ :
              $$frac{dy(theta)}{dt}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
              $dtheta=dt$
              $$frac{dy(theta)}{dtheta}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
              Thus $y(theta)$ is solution of the ODE.



              Since $y(theta)=y(t-t_0)$ this proves that $y(t-t_0)$ is also solution.






              share|cite|improve this answer









              $endgroup$
















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                $begingroup$

                $$frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$$
                Change of variable : $quadtheta=t-t_0$ :
                $$frac{dy(theta)}{dt}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
                $dtheta=dt$
                $$frac{dy(theta)}{dtheta}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
                Thus $y(theta)$ is solution of the ODE.



                Since $y(theta)=y(t-t_0)$ this proves that $y(t-t_0)$ is also solution.






                share|cite|improve this answer









                $endgroup$



                $$frac{dy(t-t_0)}{dt}=-2(y(t-t_0)-1)(y(t-t_0)-2)(y(t-t_0)-a)^2$$
                Change of variable : $quadtheta=t-t_0$ :
                $$frac{dy(theta)}{dt}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
                $dtheta=dt$
                $$frac{dy(theta)}{dtheta}=-2(y(theta)-1)(y(theta)-2)(y(theta)-a)^2.$$
                Thus $y(theta)$ is solution of the ODE.



                Since $y(theta)=y(t-t_0)$ this proves that $y(t-t_0)$ is also solution.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Jan 16 at 18:59









                JJacquelinJJacquelin

                45.8k21858




                45.8k21858






























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