I have a system of equations:

This system satisfies a relation
where is an initial condition.
For I plotted the relation y in two ways:
First way by solving the system numerically using ode45 with RelTol 1e-12 and AbsTol 1e-15 and by having the solution for x I plotted y.
Second way by solving the equation again with ode45 with Reltol 1e-9 and Abstol 1e-12 and then defining y=… and plotting it.
However, the plots are very different and I don’t understand the reason why:
Here is the plot by first method:

Here is the plot by second method:

Help is appreciated!I have a system of equations:

This system satisfies a relation
where is an initial condition.
For I plotted the relation y in two ways:
First way by solving the system numerically using ode45 with RelTol 1e-12 and AbsTol 1e-15 and by having the solution for x I plotted y.
Second way by solving the equation again with ode45 with Reltol 1e-9 and Abstol 1e-12 and then defining y=… and plotting it.
However, the plots are very different and I don’t understand the reason why:
Here is the plot by first method:

Here is the plot by second method:

Help is appreciated! I have a system of equations:

This system satisfies a relation
where is an initial condition.
For I plotted the relation y in two ways:
First way by solving the system numerically using ode45 with RelTol 1e-12 and AbsTol 1e-15 and by having the solution for x I plotted y.
Second way by solving the equation again with ode45 with Reltol 1e-9 and Abstol 1e-12 and then defining y=… and plotting it.
However, the plots are very different and I don’t understand the reason why:
Here is the plot by first method:

Here is the plot by second method:

Help is appreciated! plot, figure, ode45, differential equations, matlab MATLAB Answers — New Questions

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