Para cada uno de los siguientes sistemas encontrar todos los puntos de equilibrio y determinar el tipo de cada punto de equilibio aislado.
b)
$$\left{ \begin{array}{lcc}
\dot{x}_{1}=-x_{1}+x_{2}\\
\\ \dot{x}_{2}=\frac{x_{1}}{10}-2x_{1}-x_{1}^{2}-\frac{x_{1}^{3}}{10}
\end{array}
\right.$$
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import sympy as sym
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#Con esto las salidas van a ser en LaTeX
sym.init_printing(use_latex=True)
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x_1, x_2 = sym.symbols('x_1 x_2')
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X = sym.Matrix([x_1, x_2])
X
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f_1 = -x_1 + x_2
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f_2 = sym.Rational(1,10) * x_1 - 2 * x_2 - x_1 ** 2 - sym.Rational(1,10) * x_1 ** 3
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F = sym.Matrix([f_1,f_2])
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F
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A = F.jacobian(X)
A
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# puntos de equilibrio del sistema
pes = sym.solve([f_1,f_2])
pes
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type(pes[0])
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A_1 = A.subs(pes[0])
A_1
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A_1.eigenvals()
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A_2 = A.subs(pes[1])
A_2
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lambda_2 = A_2.eigenvals()
lambda_2
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sym.N(lambda_2.keys()[0])
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sym.N(lambda_2.keys()[1])
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A_3 = A.subs(pes[2])
A_3
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lambda_3 = A_3.eigenvals()
lambda_3
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sym.N(lambda_3.keys()[0])
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sym.N(lambda_3.keys()[1])
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